HubSpot is one of the biggest players in sales and marketing. They coined the term inbound marketing, and their content strategy has created a following that is short of cult status.
In terms of technology, HubSpot offers one of the most complete and robust CRM, marketing, and sales solutions. There’s quite a lot going on, and that’s reflected in the pricing page of HubSpot, which might initially feel more intimidating than a science degree curriculum.
To help you, I’ll start with the basics by breaking down each HubSpot plan, including the free one. Then, we’ll dive deeper into the specifics of the Sales Hub and Marketing Hub pricing and highlight some of the limitations that might not initially seem so obvious. Lastly, I’ll finish by sharing an alternative to the standard all-in-one HubSpot offering that uses third-party tools to help you save thousands of dollars (quite literally) per year.
While I cover some aspects of HubSpot’s customer service and CMS parts, this pricing guide is primarily aimed at marketers and salespeople who want to set up cohesive sales and marketing processes and automate the overall customer journey.
Let’s tune in!
Note: This post was last updated in Feb. 2025 to reflect the latest changes to the HubSpot pricing.
Contents
HubSpot pricing — the basics
HubSpot calls their plans/products “Hubs,” and as of 2025, they offer 6 hubs:
- Marketing Hub – Generate leads and automate marketing.
- Sales Hub – Build pipeline and close deals.
- Service Hub – Scale support and drive retention.
- Content Hub – Create and manage content.
- Operations Hub – Manage and activate data.
- Commerce Hub – Collect payments and subscriptions and automate billing and invoicing.
Each hub comes in 3 versions — Starter, Professional, and Enterprise. For example, “Marketing Hub Starter”.
Apart from the hubs, HubSpot offers pre-made bundles (platform solutions), which are combinations of different hubs, as well as the option to build your own bundle. These are discounted options and preferred if you need to use more than one hub.
- Starter Customer Platform – Essential marketing, sales, service, content, operations, and commerce software
- Professional Customer Platform – Advanced marketing, sales, service, content, operations, and commerce software
- Enterprise Customer Platform – Our most powerful marketing, sales, service, content, operations, and commerce software
- Marketing+ – A complete marketing solution that unites content marketing with world-class lead generation and marketing automation tools.
- Create a bundle – an option to build your own custom bundle. (Screenshot below)
Last but not least, they have the “Free Tools” option, which is essentially a bundle of all their free tools, which span across all of the hubs but are quite limited. All paid plans include all of the features in the Free Tools, so you get the free tools regardless of which hub or bundle you choose.
If you need an all-in-one solution, you can choose the “Customer Platform” bundle or create your own bundle by mixing different hubs.
You will notice that they have another plan organization, as hubs and bundles are bucketed in one of two options: “For business & enterprise” and “For individuals and small teams.” This organization is not a plan type. It’s just a way to separate the Free and Starter plans (for individuals) from the Professional and Enterprise plans (for businesses). I find adding more complexity to their pricing plan unnecessary, but they know best…
Further down this post, we’ll dive into the specifics of each hub.
How to calculate your HubSpot price?
The price you pay will be based on the tier of the hub — e.g., Starter, Professional, or Enterprise and:
- The number of Service/Market Hub seats – allows your user to use advanced features for Professional and Enterprise subscriptions.
- The number of core seats – team members with shared access to all paid features. These are the seats for the Starter set.
- The number of marketing contacts for Marketing Hub.
- Or a combination of marketing contacts and paid seats.
Here, it’s important to understand what “Core seats” are, so read the note carefully. The price for a core seat is based on the highest-tiered hub you own, as they would have access to that plan’s limits. Service and Market Hub seats are different (from Core Seats) as they give you access to the full capabilities of the Professional and Enterprise hubs.
Also, note that:
- There are additional HubSpot costs for Add-ons, usually for advanced options such as increasing list limits, extra API calls, and others.
- Some Professional and Enterprise plans require a one-time onboarding fee. For Marketing Hub Professional, it’s $3,000. Sales and Service Professional Hubs – $1,500. Marketing Enterprise – $7,000. And for Sales and Service Enterprise, it is $3,500.
- All Professional plans require a yearly commitment — either paid monthly or upfront. And all Enterprise plans require an annual commitment paid upfront.
- There are optional (one-time or monthly) onboarding, consulting, and training services that you take advantage of.
- The minimum number of seats can change depending on which plan you choose. For example, Professional plans come up with a minimum of 3 seats. This can increase your pricing additionally.
When choosing your final HubSpot plan, click on “Price breakdown” in the right sidebar to see an overview of your price:
Now, let’s examine each plan in detail, covering the pricing, critical features, and limitations.
You can refer to the official Product and Service Catalog for complete information on all HubSpot features.
HubSpot free tools features and pricing
Starts at: Free
Free tools pricing page
Previously known as simply HubSpot CRM, this plan now offers more than just a CRM. The free package provides robust contact management, sales features, forms, landing pages, live chat, email marketing, and more.
It’s a great choice if you need a fully-fledged free CRM. With its generous limit of up to 1,000,000 contacts, you can use the CRM with no critical limitations. Even without the paid features, HubSpot free CRM is a solid foundational software for your sales efforts
and a reliable single source of truth for all of your contact data.
The additional lite features are more of a teaser for the Starter and Professional plans and not really a viable alternative. Also, if you are looking to fully automate your sales cycle and marketing efforts and keep everything in one place, you’ll quickly find yourself looking at the pricing plans for the Hubs.
Important features in the Free tools plan
- Free CRM with up to 1,000,000 contacts and companies, unlimited tasks, and unlimited deals.
Unlimited users (team members)This has now been limited to 2 free seats.- Track page visits, HubSpot form submissions, and sales activity.
- Forms (with HubSpot branding).
- Landing pages (limited to 20 with HubSpot branding)
- 1-to-1 emails – connect Gmail or Outlook and send emails directly from HubSpot. You can also track replies.
- Meeting scheduling (limited to 1 meeting).
- Email marketing (up to 2,000 emails sent per month with HubSpot branding).
- Canned snippets to use in sales communication and email marketing templates (limited to 5 each).
- Live chat.
- Basic chatbots.
- One shared inbox for team email communication, such as support email and chats.
- Access to all 3rd-party apps from the HubSpot app marketplace.
- Mobile app.
- Data sync (no custom field mapping).
Limitations of the Free tools plan – HubSpot free vs. paid plan
Notable limitations
- Limited to 2 seats, users
- 10 custom properties in total – not enough for a serious business to do proper personalization
- 1 automated email per form – you can’t do lead nurturing sequences
- 1 automated action
- List segmentation: 10 active lists and 1,000 static lists – you might be able to manage with 10 dynamic lists if you don’t rely too heavily on segmentation
- Limited styling options for emails, forms, CMS assets, etc.
- Limited in sales tools (such as meetings).
- 1 shared inbox
- Limited to 1,000 marketingcontacts.
No automation features
One of the biggest limitations of both the Free and all Starter plans of HubSpot is the lack of email sequences and the Workflows feature.
No automated sales or email marketing sequences or any other type of automation. This means that you’d have to rely on manual input to manage your CRM, email, and marketing processes.
The easiest and cheapest alternative to this challenge is to connect your HubSpot CRM to an external marketing automation tool like Encharge. Read to the bottom of this post for more information.
HubSpot branding
All forms, landing pages, marketing emails, 1-to-1 sales emails, meeting pages, documents, and your live chat widget will be branded with the HubSpot logo. While the branding is not too intrusive, I still find it highly unprofessional — especially in sales-focused email communication. Imagine having the HubSpot logo on all of your sales emails.
The Sales Hub Starter plan will remove the branding from your 1-to-1 sales emails, meetings, live chat, and documents. And the Marketing Hub Starter will remove it from your marketing emails.
Alternatively, you’d need to send your personal sales email through Gmail (or another email client) and manually log them in your CRM, which is painful.
No behavioral event triggers and reporting
This one is quite important for product companies — SaaS, mobile apps, or any digital business. Without it, you won’t be able to send behavior emails or segment contacts based on what people do in your product, and you will not be able to send Webhooks or other types of event data to HubSpot.
This feature is only available on the expensive Enterprise plan, so, unfortunately, upgrading to one of the Starter or Professional plans won’t solve the issue.
However, you can connect SaaS-focused marketing automation like Encharge as an extension to your HubSpot CRM and get powerful behavior emails with excellent CRM. Learn more on the topic in our HubSpot Marketing Automation for SaaS Review.
Limited email marketing
While you can send one-time newsletters with the free plan, it’s really just limited to 2,000 emails per month (note that this is emails, not contacts). Simply not enough for even a tiny list of contacts.
Poor features for large-scale support operations
It is not limited to the Free tools plan alone, but (based on our personal experience) HubSpot is not a great tool for customer support.
Even its paid plans lack some critical features, such as the option to continue a chat conversation via email. E.g., suppose you miss a chat conversion. In that case, you’d have to manually create a ticket to be able to respond to the person via email instead of simply responding to the chat conversation. Something that even the most basic support platforms support out of the box.
While it’s great to have your support conversations in one single timeline with the rest of the lead/user interactions, I consider the customer service aspect of HubSpot quite half-baked and extremely unintuitive.
If you use live chat or chatbots to qualify leads or simply need a free chat widget that connects with your CRM, HubSpot is a good option. Otherwise, we don’t see it as a viable go-to solution for large-scale support operations.
No built-in calling feature
The calling feature is limited to 15 minutes per user per month — it’s really more of a free trial than a freemium feature.
Lack of SEO and social marketing features
I’ve never been a huge fan of using HubSpot as a CMS or SEO tool, but you can do that. However, not on the free or Starter plans as they don’t give you access to the Blog feature or any other SEO-focused features. You also won’t get access to the social scheduling feature. These are only available on Professional and Enterprise.
Other limitations
Other less-known but important to consider limitations include:
- CRM limited to 1 sales pipeline. If you have complex sales operations that depend on multiple pipelines, you’d need to upgrade to one of the paid plans.
- Active lists limited to 10. Active lists in HubSpot are dynamic segments or groups of people — i.e., contacts enter and exist active lists automatically. The free plan is limited to 5 only. Starter plan unlocks 25, and the Professional plan 1,000.
- Custom properties limited to 10. If you depend on a vast array of custom contact or company properties, the free plan won’t be the right fit for you.
- Hidden fields not available in pop-up forms. You can only add hidden fields to inline forms, but not pop-up forms. You’d need Starter Plan to unlock this feature.
- Data sync feature limited only to mapping standard HubSpot properties and not custom fields.
HubSpot Sales Hub features and pricing
Pricing
- Starter – $20/mo per seat
- Professional – $100/mo per seat | Yearly commitment | $1,500 one-time onboarding fee
- Enterprise – $150/mo per seat | Yearly commitment, paid upfront | $3,500 one-time onboarding fee
The Sales Hub Starter plan will give superpowers to your CRM and help you improve your lead management and sales processes. It’s our favorite HubSpot plan, but we might be a bit biased.
Combining it with a robust 3rd-party marketing automation platform like Encharge, you get the best overall value for money sales/marketing stack.
Great Sales Hub features
Remove HubSpot branding
You can now send sales emails without the annoying HubSpot logo in your signature. The branding is also lifted from the meeting scheduling, the chat widget, and your documents.
Sales process features
Sales conversation routing, and repeating tasks, and task queues are certainly helpful features for the larger sales-focused teams.
Higher limits for custom properties, snippets, email templates, meetings, and documents
With Sales Hub Starter and above, you lift most of the limits on these items to a comfortable number.
You get:
- 1,000 custom properties and personal & team meeting links
- 5,000 snippets, email templates, and documents
- Unlimited email open and click notifications
- 2 deal pipelines
Limitations of Sales Hub
Sales automation (only available on Professional and Enterprise)
Sales Hub Professional will unlock email sequences, and the popular Workflows feature. However, apart from the hefty price and required annual commitment with Professional, you also need to consider one other limitation when it comes to sales automation.
All emails sent through your Sales Hub plan will be sent through your Google Workspace or Outlook email accounts. You have to connect your email directly to HubSpot and use it to send emails. That’s what HubSpot refers to as 1-to-1 emails or personalized emails.
In other words, you can’t use Sales Hub to send mass marketing emails or automated welcome, onboarding, or lead nurturing emails. Your Gmail account will only allow you to send up to 200 emails per day, and you should only use sequences and Workflows for personalized sales communication at scale, not marketing. For the latter, HubSpot has Marketing Hub and a completely different pricing structure based on the number of marketing contacts.
Fortunately, an easy workaround for this is to connect a marketing automation platform like Encharge and automate the email marketing part in the external platform.
No behavioral event triggers and reporting
Similar to the free plan, the Sales Hub does not allow you to send behavior events or Webhooks to HubSpot. Not even on the Enterprise plan!
If you are a SaaS business and, for instance, want to build your sales processes around PQLs (product qualified leads) you will be in no luck with the Sales Hub plan. You’d need the Marketing Hub Enterprise for this, and things get very, very expensive.
Custom objects only available on Enterprise
Custom objects in CRM tools allow you to manage other types of entities that are not contacts or companies. For instance, if you are a franchise business, you might manage “stores” or “locations”.
Unfortunately, custom objects are only available on the Sales Hub Enterprise plan, which starts at $1,800 per seat per year.
Pro tip: Go with a marketing automation platform that offers Custom objects for as low as $159 per month and integrate your HubSpot account with it.
HubSpot Marketing Hub features and pricing
Pricing
- Starter – $20/mo per seat (first seat includes 1,000 marketing contacts). | Additional marketing contacts are sold in increments of 1,000 from $50/month. | Additional seats cost $20/mo
- Professional – $890/mo with 2,000 marketing contacts and 3 seats. | Additional marketing contacts are sold in increments of 5,000 from $250/month. | Additional seats cost $50/mo. | Annual commitment | Onboarding fee – $3,000
- Enterprise – $3,600/mo with 10,000 marketing contacts and 5 seats. | Additional marketing contacts are sold in increments of 10,000 from $100/month. | Additional seats cost $75/mo | Onboarding fee – $7,000
The Marketing Hub is geared towards experienced marketers and provides a full suite of marketing tools including workflows, account-based marketing automation, social media, video hosting, SEO tools, and content tools such as blogs.
As you probably noticed, the Marketing Hub is significantly more expensive than the Sales Hub — at $890/mo for 2,000 marketing contacts; you have to be prepared to pay around a $13,000 (annual plan + $3,000 one-time onboarding fee) to get access to the Professional plan. And that’s just for a small email list of fewer than 2k contacts. Additional 5,000 contacts start at $250/mo.
To better calculate your pricing, you need to understand what HubSpot deems a “marketing contact”. Here’s a blurb taken from their services catalog:
Marketing Contacts: Marketing contacts can be sent marketing emails and be targeted with ads manually or with automation if it’s included in your subscription.
Non-Marketing Contacts: Non-marketing contacts cannot be sent marketing emails and cannot be targeted with ads.
In other words, your CRM contacts do not count towards this number until you start sending them marketing emails.
The reason for this pricing is pretty simple — marketing emails, unlike direct 1:1 sales emails, are not sent from your Gmail or Outlook account but from the HubSpot email servers.
Great Marketing Hub features
Marketing automation with workflows
The Professional plan unlocks the marketing automation workflows in HubSpot and is by far the most useful and valuable feature of the Marketing Hub. It’s very tightly connected with the rest of the platform and allows you to automate a lot of the sales processes in your CRM.
Unfortunately, this and all of the cool features are only available on the Professional plan alone.
Other significant features include:
- Social media scheduling
- Blog
- Add retargeting
- SEO optimization tools
- Landing page A/B testing
- ABM automation such as company scoring, properties, and more
- Website analytics ala Google Analytics
Limitations of Marketing Hub
Pretty limited Starter Plan
The Marketing Hub Starter plan doesn’t really unlock any major features. It only increases the number of emails you can send per month as well as the number of marketing contacts. It also unlocks other limits like 50 active and 1000 static lists, up to 10 automated actions for email automation, and simple ad and form automation.
Plus, it removes branding from forms, landing pages, and marketing emails. However, note that your sales emails (i.e., 1-to-1 emails) you send directly through the CRM will still have the HubSpot logo, so you still need to buy a Sales Hub Starter plan.
Essentially, you can set up more basic automations for forms and emails (by accessing the form and email settings), but you still don’t have access to the Workflow builder, which they call “Omni-channel automation”. You’d need to jump on the Professional plan if you are looking for proper automation.
Behavioral event triggers and reporting only available on Enterprise plan
Unlike the Sales Hub, the Marketing Hub actually unlocks behavior-based emailing and Webhooks (called “Custom events” feature in HubSpot). However, they are only available on the Enterprise plan, starting at a hefty $43,200 per year paid upfront + $7,000 onboarding fee. And let’s not forget that this plan only gives you 10,000 marketing contacts.
Again, a solution is to use an external marketing automation platform like Encharge that is geared towards SaaS companies and plays nicely with HubSpot.
Read more: HubSpot Marketing Hub: Features and comparison with Mailchimp and Encharge
Service Hub features and pricing
Pricing
- Starter – $20/mo per seat
- Professional – $100/mo per seat | Annual commitment | $1,500 onboarding fee
- Enterprise – $150/mo per seat. | Annual commitment paid upfront | $3,500 onboarding fee
As we covered earlier in this post, we are not huge fans of the service-focused features of HubSpot. It has some major UX issues, like not being able to continue a chat conversation via email without having to jump through hoops like manually creating tickets.
Other issues include:
- The lack of tags on conversations
- Inability to see if another user (team member) is in the ticket
- When a person responds to a closed ticket, the ticket doesn’t open automatically.
- You can’t use HubSpot forms to populate custom Ticket properties, which renders them almost useless to collect information about the customer’s problem.
The chat and ticketing features are quite limited and, in many cases, counter-intuitive to use. It almost feels like this aspect of the platform was rushed out and half-baked, especially compared to other hubs.
While it’s great to have cohesion with the rest of the HubSpot platform and be able to track support conversations in one centralized place, the Service Hub is not yet up to par with a dedicated support platform.
If you still decide to go with it, it offers a wide range of features such as shared inbox, ticketing, live chat, knowledgebase, NPS, other types of surveys, and even support SLAs, ticket routing and help desk automation.
Content Hub features and pricing
Pricing
- Starter – $20/mo per seat
- Professional – $500/mo with 3 seats included | $50/mo for an additional core seat | Yearly commitment
- Enterprise – $1,500/mo with 5 seats included | $75/mo for an additional core seat | Yearly commitment, paid upfront
The Content Hub is aimed at bloggers and content creators.
The Starter plan gives you advanced domain and hosting features such as CDN, SSL certificate, scalable hosting. It also unlocks more design-builder options such as themes and drag-and-drop editor.
The Professional plan expands this feature set with “Smart content” and Dynamic personalization, allowing you to dynamically change your website and personalize your website experience with data from your CRM, A/b testing for web pages, and SEO tools.
Operations Hub features and pricing
Pricing
- Starter – $20/mo per seat
- Professional – $800/mo with 1 seat included | $50/mo for an additional core seat | Yearly commitment
- Enterprise – $2,000/mo with 1 seat | $75/mo for an additional core seat | Yearly commitment, paid upfront
The Operations Hub is the latest addition to the HubSpot family. It was introduced after HubSpot acquired data syncing startup Piesync. It allows you to sync data between HubSpot and 3rd party apps.
The biggest advantage of the paid plans over the free syncing is that it allows you to sync custom properties, while the free version only allows you to sync the standard HubSpot fields.
Another great addition is access to Webhooks — the capability to send HubSpot data to external tools. Unfortunately, it comes with the Professional plan only and a hefty $800/mo price tag.
HubSpot pricing and additional costs table
Price | Commitment | Onboarding fee (one-time) | Features | |
---|---|---|---|---|
Free Tools | Free | No | No | Free CRM with up to 1,000,000 contacts and companies, unlimited tasks, unlimited deals, and 2 users. Site tracking, forms, landing pages, 1-to-1 emails, 1 meeting scheduling, 1,000 contacts email marketing, data sync. |
MARKETING HUB | ||||
Starter | $20/mo per seat (first seat includes 1,000 marketing contacts). | Additional marketing contacts are sold in increments of 1,000 from $50/month. | Additional seats cost $20/mo | No | No | Removes branding from forms, email marketing, landing pages, live chat |
Professional | $890/mo with 2,000 marketing contacts and 3 seats. | Additional marketing contacts are sold in increments of 5,000 from $250/month. | Additional seats cost $50/mo. | Yearly | $3,000 | Omni-channel marketing automation, ABM tools and automation, Dynamic personalization, Multi-language content, Social media, Video hosting,Contact and company scoring, A/B testing, reports |
Enterprise | $3,600/mo with 10,000 marketing contacts and 5 seats. | Additional marketing contacts are sold in increments of 10,000 from $100/month. | Additional seats cost $75/mo | Yearly. Paid upfront | $7,000 | Custom objects, behavior emails and Webhooks, predictive lead scoring, advanced team permissions, multi-touch revenue attribution |
SALES HUB | ||||
Starter | $20/mo per seat | No | No | Remove branding from live chat, meeting scheduling, documents, 1-to-1 email Conversation routing, repeating tasks and task queues, Stripe integration and more |
Professional | $100/mo per seat | Yearly | $1,500 | Sales sequences, sales workflows, sales analyticsTeams, custom reporting, ABM tools, eSignature, and more. |
Enterprise | $150/mo per seat | Yearly. Paid upfront | $3,500 | Custom objects, predictive lead scoring, advanced permissions |
SERVICE HUB | ||||
Starter | $20/mo per seat | No | No | Remove branding from live chat, meeting scheduling, documents, 1-to-1 email Shared inbox, mobile inbox, team email, ticket pipelines |
Professional | $100/mo per seat | Yearly | $1,500 | Knowledgebase, help desk automation, ticket routing, SLAs, NPS surveys and other surveys, customer portal |
Enterprise | $150/mo per seat | Yearly. Paid uprfront | $3,500 | Permission sets, custom objects, goals, playbooks |
CONTENT HUB | ||||
Starter | $20/mo per seat | No | No | Premium hosting, CDN, SSL, WAF, themes, drag and drop builder |
Professional | $500/mo with 3 seats included | $50/mo for an additional core seat | Yearly | No | Smart content and reporting, dynamic personalization, password-protected pages, A/b website testing, SEO tools, content strategy |
Enterprise | $1,200/mo | Yearly. Paid upfront | No | Custom objects, memberships |
OPERATIONS HUB | ||||
Starter | $20/mo per seat | No | No | Custom field mappings and custom properties |
Professional | $800/mo with 1 seat included | $50/mo for an additional core seat | Yearly | No | Programmable automation, Webhooks, scheduled workflow triggers |
Enterprise | $2,000/mo with 1 seat included | $75/mo for an additional core seat | Yearly. Paid upfront | Datasets, advanced data calculations and prep, custom objects |
How to save on HubSpot pricing with an affordable alternative that plays nicely with your CRM
We built Encharge as an affordable marketing automation alternative that plays nicely with the Free Tools and the Sales Hub of HubSpot. Encharge is a powerful marketing automation tool built for digital businesses that integrates deeply with HubSpot and provides a cost-effective alternative to the HubSpot Marketing Hub.
Now you can use your HubSpot CRM and supercharge it with the marketing automation of Encharge, starting at just $159/month for 2,000 contacts.
Here’s how Encharge stacks against HubSpot Marketing Hub:
As you can see, you can save more than $7,000 a year.
The ideal stack we recommend is HubSpot Sales Hub Starter + Encharge Premium.
For $159 a month with Encharge Premium, you get:
- Fast two-way sync of HubSpot contacts and companies — all of your HubSpot contact and company data automatically synced to Encharge and the other way around.
- 13 different automation steps to build and automate your HubSpot processes. A great alternative to HubSpot Sales Hub Professional.
- All of your email marketing activity from Encharge synced to HubSpot. See which leads open, click, and reply to your marketing emails and build active lists using email marketing activity.
- Easy to use but powerful flow builder (the perfect alternative to HubSpot workflows).
- Ability to build marketing automations with external tools like Segment, Stripe, Typeform, Facebook Ads, Intercom, Salesforce, and more. Check out the integrations we support.
- Behavior-based emails and Webhooks (only available on HubSpot Marketing Hub Enterprise). Must-have for SaaS companies.
- The most powerful user and lead segmentation on the market.
To learn more about how Encharge works with HubSpot, check out our HubSpot integration page.
Some of the things you can do with Encharge + HubSpot include:
- Automatically send your HubSpot CRM contacts to Encharge.
- Create new deals in HubSpot when a contact is created or updated in Encharge.
- Update deal stage in HubSpot based on activity in Encharge or other tools in your marketing stack
- Start sending lead nurturing emails to contacts that enter a HubSpot list.
- Start an Encharge flow when someone books a meeting or submits a HubSpot form.
- Automate the lifecycle stages.
Want to take Encharge for a spin? Register for a free 14-day trial or book a free strategy call with us and let us help you with your marketing stack.