GrowthBook
@growthbook.io
GrowthBook is an open-source feature flagging and experimentation platform. www.growthbook.io
Ever wonder if your feature actually moved the needle, or if that metric bump was just seasonal variance?
Most teams struggle with this because they can't isolate the real impact of their changes.
That's where holdouts come in - and why we just shipped them in GrowthBook.
What are holdouts?
Most teams struggle with this because they can't isolate the real impact of their changes.
That's where holdouts come in - and why we just shipped them in GrowthBook.
What are holdouts?
How GrowthBook Holdouts Work Under the Hood
Most holdouts measure only shipped features. Ours measure everything—including failed experiments. This technical deep dive reveals why we chose reality over clean rooms, and how we built it.
blog.growthbook.io
September 24, 2025 at 7:14 PM
Ever wonder if your feature actually moved the needle, or if that metric bump was just seasonal variance?
Most teams struggle with this because they can't isolate the real impact of their changes.
That's where holdouts come in - and why we just shipped them in GrowthBook.
What are holdouts?
Most teams struggle with this because they can't isolate the real impact of their changes.
That's where holdouts come in - and why we just shipped them in GrowthBook.
What are holdouts?
Yesterday's comic was, of course, in reference to Twyman's Law.
Applicable not only to experiment analysis, but also life. If it looks too good to be true, then it probably is 😅
Applicable not only to experiment analysis, but also life. If it looks too good to be true, then it probably is 😅
September 17, 2025 at 7:14 PM
Yesterday's comic was, of course, in reference to Twyman's Law.
Applicable not only to experiment analysis, but also life. If it looks too good to be true, then it probably is 😅
Applicable not only to experiment analysis, but also life. If it looks too good to be true, then it probably is 😅
This fantastic comic (xkcd 2899) is about which law?
September 16, 2025 at 7:14 PM
This fantastic comic (xkcd 2899) is about which law?
As a company, we do things companies do:
• Run A/B tests (obviously)
• SEO
• And now, GEO - optimizing for visibility in AI searches like ChatGPT
What's GEO (Generative Engine Optimization)? We were wondering that too, so we did some research.
Here are 3 surprising findings:
• Run A/B tests (obviously)
• SEO
• And now, GEO - optimizing for visibility in AI searches like ChatGPT
What's GEO (Generative Engine Optimization)? We were wondering that too, so we did some research.
Here are 3 surprising findings:
The Definitive Technical Guide to Generative Engine Optimization (2025)
Everything you need to know about Generative Engine Optimization (GEO).
blog.growthbook.io
September 15, 2025 at 8:24 PM
As a company, we do things companies do:
• Run A/B tests (obviously)
• SEO
• And now, GEO - optimizing for visibility in AI searches like ChatGPT
What's GEO (Generative Engine Optimization)? We were wondering that too, so we did some research.
Here are 3 surprising findings:
• Run A/B tests (obviously)
• SEO
• And now, GEO - optimizing for visibility in AI searches like ChatGPT
What's GEO (Generative Engine Optimization)? We were wondering that too, so we did some research.
Here are 3 surprising findings:
This week we've been sharing everything included in our latest 4.1 release, which includes:
→ 150+ commits
→ 8 major features (holdouts, dashboards, #AI, Vercel, Pre-computed dimensions, MCP, FerretDB, Sanity)
→ 0 vendor lock-in
Curious? Full release notes: blog.growthbook.io/growthbook-v...
→ 150+ commits
→ 8 major features (holdouts, dashboards, #AI, Vercel, Pre-computed dimensions, MCP, FerretDB, Sanity)
→ 0 vendor lock-in
Curious? Full release notes: blog.growthbook.io/growthbook-v...
GrowthBook Version 4.1
GrowthBook version 4.1 includes Holdouts, Dashboards, AI features, and More!
blog.growthbook.io
September 12, 2025 at 1:01 PM
This week we've been sharing everything included in our latest 4.1 release, which includes:
→ 150+ commits
→ 8 major features (holdouts, dashboards, #AI, Vercel, Pre-computed dimensions, MCP, FerretDB, Sanity)
→ 0 vendor lock-in
Curious? Full release notes: blog.growthbook.io/growthbook-v...
→ 150+ commits
→ 8 major features (holdouts, dashboards, #AI, Vercel, Pre-computed dimensions, MCP, FerretDB, Sanity)
→ 0 vendor lock-in
Curious? Full release notes: blog.growthbook.io/growthbook-v...
We're just going to go ahead and say it: GrowthBook is the most comprehensive open-source experimentation platform.
Now with #FerretDB support.
Because open source means ALL the way down.
Learn more: docs.growthbook.io/self-host/fe...
Now with #FerretDB support.
Because open source means ALL the way down.
Learn more: docs.growthbook.io/self-host/fe...
FerretDB | GrowthBook Docs
How to use FerretDB with GrowthBook
docs.growthbook.io
September 11, 2025 at 9:24 PM
We're just going to go ahead and say it: GrowthBook is the most comprehensive open-source experimentation platform.
Now with #FerretDB support.
Because open source means ALL the way down.
Learn more: docs.growthbook.io/self-host/fe...
Now with #FerretDB support.
Because open source means ALL the way down.
Learn more: docs.growthbook.io/self-host/fe...
Sanity offers a powerful content management solution that effortlessly integrates with GrowthBook, enabling you to conduct experiments directly from your content editor without altering any code. This approach allows you to benefit from feature-flag experiments seamlessly.
A/B Testing Made Easy: Sanity + GrowthBook + Next.js Tutorial
Stop hardcoding A/B tests! Learn how to build a professional experimentation system where your content team can create and manage A/B tests directly with Sanity, while GrowthBook handles the…
www.youtube.com
September 11, 2025 at 8:24 PM
Sanity offers a powerful content management solution that effortlessly integrates with GrowthBook, enabling you to conduct experiments directly from your content editor without altering any code. This approach allows you to benefit from feature-flag experiments seamlessly.
GrowthBook is now native on Vercel Marketplace 🎯
What this means for your Next.js apps:
→ One-click installation
→ Unified billing (one less vendor to manage)
→ Edge-ready performance (we're talking microseconds)
→ Feature flags that actually work at the edge
What this means for your Next.js apps:
→ One-click installation
→ Unified billing (one less vendor to manage)
→ Edge-ready performance (we're talking microseconds)
→ Feature flags that actually work at the edge
GrowthBook for Vercel – Vercel
Open source experimentation and feature flag management.
vercel.com
September 10, 2025 at 8:24 PM
GrowthBook is now native on Vercel Marketplace 🎯
What this means for your Next.js apps:
→ One-click installation
→ Unified billing (one less vendor to manage)
→ Edge-ready performance (we're talking microseconds)
→ Feature flags that actually work at the edge
What this means for your Next.js apps:
→ One-click installation
→ Unified billing (one less vendor to manage)
→ Edge-ready performance (we're talking microseconds)
→ Feature flags that actually work at the edge
We've introduced practical AI features in GrowthBook 4.1:
🤖 Auto-summarize experiment results
📊 Generate SQL queries from natural language
💡 Enhance experiment hypotheses with AI
🔍 Automatically find similar past experiments
➕ Customize prompts for your org
🙅 Prefer no AI? Disable it entirely.
🤖 Auto-summarize experiment results
📊 Generate SQL queries from natural language
💡 Enhance experiment hypotheses with AI
🔍 Automatically find similar past experiments
➕ Customize prompts for your org
🙅 Prefer no AI? Disable it entirely.
September 10, 2025 at 7:14 PM
We've introduced practical AI features in GrowthBook 4.1:
🤖 Auto-summarize experiment results
📊 Generate SQL queries from natural language
💡 Enhance experiment hypotheses with AI
🔍 Automatically find similar past experiments
➕ Customize prompts for your org
🙅 Prefer no AI? Disable it entirely.
🤖 Auto-summarize experiment results
📊 Generate SQL queries from natural language
💡 Enhance experiment hypotheses with AI
🔍 Automatically find similar past experiments
➕ Customize prompts for your org
🙅 Prefer no AI? Disable it entirely.
Your PM: "What happened with that experiment?"
You: Opens 17 tabs, 3 spreadsheets, and a Slack thread
Sound familiar? We fixed that.
Introducing Experiment Dashboards in GrowthBook 4.1:
✅ Create custom views
✅ Highlight metrics
✅ Add context
✅ Share a single link instead of a dissertation
You: Opens 17 tabs, 3 spreadsheets, and a Slack thread
Sound familiar? We fixed that.
Introducing Experiment Dashboards in GrowthBook 4.1:
✅ Create custom views
✅ Highlight metrics
✅ Add context
✅ Share a single link instead of a dissertation
September 9, 2025 at 8:24 PM
Your PM: "What happened with that experiment?"
You: Opens 17 tabs, 3 spreadsheets, and a Slack thread
Sound familiar? We fixed that.
Introducing Experiment Dashboards in GrowthBook 4.1:
✅ Create custom views
✅ Highlight metrics
✅ Add context
✅ Share a single link instead of a dissertation
You: Opens 17 tabs, 3 spreadsheets, and a Slack thread
Sound familiar? We fixed that.
Introducing Experiment Dashboards in GrowthBook 4.1:
✅ Create custom views
✅ Highlight metrics
✅ Add context
✅ Share a single link instead of a dissertation
The issue with A/B tests? They conclude. But what about tracking the combined effect of 50 updates over six months? Enter Holdouts: the perpetual experiment. Keep 5% of users on the initial experience, while others enjoy new features. Gauge the true long-term impact of your product changes.
Holdouts in GrowthBook: The Gold Standard for Measuring Cumulative Impact
Many teams ship features weekly but struggle to measure their true cumulative impact. Holdouts in GrowthBook provide a simple way to maintain a control group across multiple features, answering the…
blog.growthbook.io
September 9, 2025 at 7:14 PM
The issue with A/B tests? They conclude. But what about tracking the combined effect of 50 updates over six months? Enter Holdouts: the perpetual experiment. Keep 5% of users on the initial experience, while others enjoy new features. Gauge the true long-term impact of your product changes.
Most holdouts measure only shipped features. Ours measure everything—including failed experiments.
Because that's what your users actually experienced.
Technical breakdown → blog.growthbook.io/holdouts-dee...
Because that's what your users actually experienced.
Technical breakdown → blog.growthbook.io/holdouts-dee...
How GrowthBook Holdouts Work Under the Hood
Most holdouts measure only shipped features. Ours measure everything—including failed experiments. This technical deep dive reveals why we chose reality over clean rooms, and how we built it.
blog.growthbook.io
September 4, 2025 at 12:45 PM
Most holdouts measure only shipped features. Ours measure everything—including failed experiments.
Because that's what your users actually experienced.
Technical breakdown → blog.growthbook.io/holdouts-dee...
Because that's what your users actually experienced.
Technical breakdown → blog.growthbook.io/holdouts-dee...
Experiments showed +5%, +3%, +7% wins, but do they really add up to +15%? Likely not, as Airbnb found naive sums can overstate impact by 2x. GrowthBook now offers ✨ Holdouts ✨ for accurate metric measurement:
Holdouts in GrowthBook: The Gold Standard for Measuring Cumulative Impact
Many teams ship features weekly but struggle to measure their true cumulative impact. Holdouts in GrowthBook provide a simple way to maintain a control group across multiple features, answering the…
blog.growthbook.io
September 3, 2025 at 8:24 PM
Experiments showed +5%, +3%, +7% wins, but do they really add up to +15%? Likely not, as Airbnb found naive sums can overstate impact by 2x. GrowthBook now offers ✨ Holdouts ✨ for accurate metric measurement:
Another big week for the experimentation industry: OpenAI has acquired Statsig for 1.1B.
Graham shares his thoughts on the acquisition and our new Statsig to GrowthBook migration kit:
www.linkedin.com/posts/graham...
Graham shares his thoughts on the acquisition and our new Statsig to GrowthBook migration kit:
www.linkedin.com/posts/graham...
Announcing the Statsig to GrowthBook Migration Kit
For those customers who want more certainty and innovation from their experimentation platform, I’m happy to announce the Statsig to GrowthBook Migration Kit. This kit allows customers to migrate from Statsig to GrowthBook in minutes. Customers will be able to import all projects, environments, and feature flags. Imports will include fallback values, targeting rules, rollouts, and prerequisite features.
www.linkedin.com
September 3, 2025 at 7:14 PM
Another big week for the experimentation industry: OpenAI has acquired Statsig for 1.1B.
Graham shares his thoughts on the acquisition and our new Statsig to GrowthBook migration kit:
www.linkedin.com/posts/graham...
Graham shares his thoughts on the acquisition and our new Statsig to GrowthBook migration kit:
www.linkedin.com/posts/graham...
It's possible to build beautiful sites with Framer. But how do you know if they actually convert?
You don't unless you test! Our official plugin for Framer lets you do enterprise-level experimentation on your components.
Our tutorial helps you get set up in minutes. youtu.be/XqHDLbYCfTM?...
You don't unless you test! Our official plugin for Framer lets you do enterprise-level experimentation on your components.
Our tutorial helps you get set up in minutes. youtu.be/XqHDLbYCfTM?...
Add Pro A/B Testing to Framer in Minutes (GrowthBook Plugin)
Stop guessing what converts. Start knowing.
In this tutorial, I show you how to add enterprise-level A/B testing to your #framer site in minutes using the GrowthBook plugin. No coding required,…
youtu.be
August 27, 2025 at 7:14 PM
It's possible to build beautiful sites with Framer. But how do you know if they actually convert?
You don't unless you test! Our official plugin for Framer lets you do enterprise-level experimentation on your components.
Our tutorial helps you get set up in minutes. youtu.be/XqHDLbYCfTM?...
You don't unless you test! Our official plugin for Framer lets you do enterprise-level experimentation on your components.
Our tutorial helps you get set up in minutes. youtu.be/XqHDLbYCfTM?...
It's a hard truth—but we're not all SQL geniuses.
Get a little (or lot of help) with your next query by using our new natural language to SQL generation feature. Ask, for example, to list the top 10 pages by view count in the past 3 months and get back a crisp SELECT statement.
See Graham's demo
Get a little (or lot of help) with your next query by using our new natural language to SQL generation feature. Ask, for example, to list the top 10 pages by view count in the past 3 months and get back a crisp SELECT statement.
See Graham's demo
August 22, 2025 at 3:02 PM
It's a hard truth—but we're not all SQL geniuses.
Get a little (or lot of help) with your next query by using our new natural language to SQL generation feature. Ask, for example, to list the top 10 pages by view count in the past 3 months and get back a crisp SELECT statement.
See Graham's demo
Get a little (or lot of help) with your next query by using our new natural language to SQL generation feature. Ask, for example, to list the top 10 pages by view count in the past 3 months and get back a crisp SELECT statement.
See Graham's demo
Teams often struggle with an ever-growing list of metrics, ballooning from 20 to 200. Finding a specific metric during a new experiment can be tough, leading to even more creation ☠️. AI can automatically summarize metrics, making them easier to find and preventing duplicates. Watch Graham's demo 👇
August 21, 2025 at 7:14 PM
Teams often struggle with an ever-growing list of metrics, ballooning from 20 to 200. Finding a specific metric during a new experiment can be tough, leading to even more creation ☠️. AI can automatically summarize metrics, making them easier to find and preventing duplicates. Watch Graham's demo 👇
Hypothesis enforcement just dropped ✨
No, you won't get a ticket for sloppy hypotheses—but this AI-powered feature ensures your team writes them right.
YOU set the quality bar. Academic rigor or lighter touch, your choice.
Don't just run experiments, run them right.
No, you won't get a ticket for sloppy hypotheses—but this AI-powered feature ensures your team writes them right.
YOU set the quality bar. Academic rigor or lighter touch, your choice.
Don't just run experiments, run them right.
August 19, 2025 at 8:24 PM
Hypothesis enforcement just dropped ✨
No, you won't get a ticket for sloppy hypotheses—but this AI-powered feature ensures your team writes them right.
YOU set the quality bar. Academic rigor or lighter touch, your choice.
Don't just run experiments, run them right.
No, you won't get a ticket for sloppy hypotheses—but this AI-powered feature ensures your team writes them right.
YOU set the quality bar. Academic rigor or lighter touch, your choice.
Don't just run experiments, run them right.
Automatic experiment result summary generation is here 🪄 Get a summary of your experiment results instantly, including key findings based on your metrics and variants, that's totally customizable to your organization's style and requirements.
August 19, 2025 at 7:14 PM
Automatic experiment result summary generation is here 🪄 Get a summary of your experiment results instantly, including key findings based on your metrics and variants, that's totally customizable to your organization's style and requirements.
Here's the tutorial you've been looking for: #Sanity + #Next.js + GrowthBook
Ryan provides a comprehensive walkthrough of everything you need to know to set up an enterprise-grade experimentation system that everyone on the team can use!
youtu.be/tg85K9K_8-g
Ryan provides a comprehensive walkthrough of everything you need to know to set up an enterprise-grade experimentation system that everyone on the team can use!
youtu.be/tg85K9K_8-g
A/B Testing Made Easy: Sanity + GrowthBook + Next.js Tutorial
Stop hardcoding A/B tests! Learn how to build a professional experimentation system where your content team can create and manage A/B tests directly with Sanity, while GrowthBook handles the…
youtu.be
August 18, 2025 at 8:24 PM
Here's the tutorial you've been looking for: #Sanity + #Next.js + GrowthBook
Ryan provides a comprehensive walkthrough of everything you need to know to set up an enterprise-grade experimentation system that everyone on the team can use!
youtu.be/tg85K9K_8-g
Ryan provides a comprehensive walkthrough of everything you need to know to set up an enterprise-grade experimentation system that everyone on the team can use!
youtu.be/tg85K9K_8-g
Graham and Ryan demo all the new AI-powered features recently released in GrowthBook.
The best part? Every AI prompt is fully customizable. Want results in haikus? Different language? Your company's tone of voice? You control it all.
youtu.be/jhyGxknbGk0
The best part? Every AI prompt is fully customizable. Want results in haikus? Different language? Your company's tone of voice? You control it all.
youtu.be/jhyGxknbGk0
Introducing GrowthBook AI: 6 New Features for Smarter Experimentation
Discover how GrowthBook is revolutionizing A/B testing and experimentation with powerful AI features! In this demo, GrowthBook CEO Graham and Developer Advocate Ryan showcase the latest AI-powered…
youtu.be
August 18, 2025 at 7:14 PM
Graham and Ryan demo all the new AI-powered features recently released in GrowthBook.
The best part? Every AI prompt is fully customizable. Want results in haikus? Different language? Your company's tone of voice? You control it all.
youtu.be/jhyGxknbGk0
The best part? Every AI prompt is fully customizable. Want results in haikus? Different language? Your company's tone of voice? You control it all.
youtu.be/jhyGxknbGk0
New tutorial: Run A/B tests without deploying code 🚀
Connect @sanity_io + GrowthBook + Next.js so content editors can test directly from Sanity Studio.
No more eng bottlenecks for headline tests.
Guide → docs.growthbook.io/guide/sanity
What integration should we build next?
Connect @sanity_io + GrowthBook + Next.js so content editors can test directly from Sanity Studio.
No more eng bottlenecks for headline tests.
Guide → docs.growthbook.io/guide/sanity
What integration should we build next?
August 12, 2025 at 7:14 PM
New tutorial: Run A/B tests without deploying code 🚀
Connect @sanity_io + GrowthBook + Next.js so content editors can test directly from Sanity Studio.
No more eng bottlenecks for headline tests.
Guide → docs.growthbook.io/guide/sanity
What integration should we build next?
Connect @sanity_io + GrowthBook + Next.js so content editors can test directly from Sanity Studio.
No more eng bottlenecks for headline tests.
Guide → docs.growthbook.io/guide/sanity
What integration should we build next?
The velocity of change is changing.
🚗 Ford Model T → 1 million sold: 13 years
🔎 Google → 1 million searches/day: 1 year
📱 iPhone → 1 million units: 74 days
💬 ChatGPT → 1 billion searches/day: <1 year
This isn't just acceleration—it's a fundamental shift in how quickly markets transform.
🚗 Ford Model T → 1 million sold: 13 years
🔎 Google → 1 million searches/day: 1 year
📱 iPhone → 1 million units: 74 days
💬 ChatGPT → 1 billion searches/day: <1 year
This isn't just acceleration—it's a fundamental shift in how quickly markets transform.
August 6, 2025 at 1:30 PM
The velocity of change is changing.
🚗 Ford Model T → 1 million sold: 13 years
🔎 Google → 1 million searches/day: 1 year
📱 iPhone → 1 million units: 74 days
💬 ChatGPT → 1 billion searches/day: <1 year
This isn't just acceleration—it's a fundamental shift in how quickly markets transform.
🚗 Ford Model T → 1 million sold: 13 years
🔎 Google → 1 million searches/day: 1 year
📱 iPhone → 1 million units: 74 days
💬 ChatGPT → 1 billion searches/day: <1 year
This isn't just acceleration—it's a fundamental shift in how quickly markets transform.
The AI Revolution Isn't Our First Rodeo 🎢
When electricity arrived in the 1880s, most factories just swapped steam engines for electric motors. Same layout. Same processes. Electric lightbulbs where gas lamps used to be.
Then Henry Ford reimagined everything.
When electricity arrived in the 1880s, most factories just swapped steam engines for electric motors. Same layout. Same processes. Electric lightbulbs where gas lamps used to be.
Then Henry Ford reimagined everything.
Building in the AI Era: Lessons from Past Technological Revolutions
Why bolting AI onto existing products is like adding lightbulbs to steam factories. Lessons from Ford to ChatGPT on truly transformative tech adoption.
blog.growthbook.io
August 5, 2025 at 7:14 PM
The AI Revolution Isn't Our First Rodeo 🎢
When electricity arrived in the 1880s, most factories just swapped steam engines for electric motors. Same layout. Same processes. Electric lightbulbs where gas lamps used to be.
Then Henry Ford reimagined everything.
When electricity arrived in the 1880s, most factories just swapped steam engines for electric motors. Same layout. Same processes. Electric lightbulbs where gas lamps used to be.
Then Henry Ford reimagined everything.
Cut feature flag latency to practically zero when you integrate GrowthBook with @Vercel Edge Config.
Here's why it's a game changer for technical teams:
Here's why it's a game changer for technical teams:
July 31, 2025 at 1:05 PM
Cut feature flag latency to practically zero when you integrate GrowthBook with @Vercel Edge Config.
Here's why it's a game changer for technical teams:
Here's why it's a game changer for technical teams: