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Flagsmith

Open-source feature flags, remote config and A/B testing

  • Researched profile
  • Free plan
  • Open source
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Starting price
Free open-source edition; hosted plan prices not confirmed from search results
Free option
Free plan
Pricing
Free
Licence
Open source
Deployment
Web, Self-hosted
Integrations
1 listed

The lean-stack take

For a lean product team it supports validated learning. A team releases a change to one group of users behind a flag, measures the result, then keeps or removes it.

Best for

Product and engineering teams that want feature flags and A/B tests with the option to self-host open-source code.

Watch out for

Test results come from the experimentation feature or a connected analytics tool, so check how you will measure each experiment before you start.

About

About Flagsmith

Flagsmith is an open-source feature flag platform with remote config and experimentation. Its GitHub repository describes self-hosted and cloud deployment options.

Written by lean-stack from Flagsmith's public pages. Vendors can replace it with their own description by claiming this profile.

Features

What Flagsmith offers

01

Feature flags

The docs cover creating feature flags and managing their lifecycle. Flags let a team release in small batches and switch a change off quickly.

02

Remote config

The GitHub repository lists remote config alongside flags. Teams can change values such as copy or limits without a new release.

03

Segments

Segments target flags at groups of users by their traits. A help article discusses using segment data from tools such as Mixpanel.

04

Multivariate flags

A vendor blog post introduces multivariate flags for A/B testing and canary deployments. Each variation is served to a share of users.

05

Experimentation

The docs have an experimentation section with a guide to creating an experiment. A separate page covers A/B testing with analytics integrations.

06

Open source and self-hosting

Flagsmith publishes its code on GitHub and has pages on open-source and self-hosted use. Teams with strict data rules can run it on their own infrastructure.

07

Access and change control

A product page covers role-based access, change control and security. A team can review a flag change before it reaches users.

08

Integrations

An integrations page lists built-in third-party integrations, and the docs cover a webhook integration.

Lean techniques supported

The lean practices Flagsmith is built to support.

Pricing

Flagsmith pricing

Checked October 29, 2026

Starting price

Free open-source edition; hosted plan prices not confirmed from search results

Pricing
Free
Free option
Free plan

How pricing works

Flagsmith offers open-source self-hosting and hosted plans listed on its pricing page; check the page for current prices and limits.

Flagsmith publishes a pricing page and an enterprise page; current prices were not visible in search results. The open-source code on GitHub can be self-hosted.

See current prices on flagsmith.com

Flagsmith doesn't publish a full plan list, so we show what it does publish. Confirm prices with the vendor.

Strengths and limitations

What stands out, and what to watch

Strengths

  • Open-source code on GitHub that can be self-hosted
  • Feature flags, remote config and segments in one tool
  • Multivariate flags for A/B tests and canary releases
  • Experimentation docs, including a guide to creating an experiment
  • Role-based access and change control

Limitations

  • Hosted plan prices and limits not confirmed from search results
  • Named integrations other than webhooks not confirmed from search results
  • Founding year and headquarters not confirmed from search results
  • G2 and Capterra ratings not shown in search results

Based on the vendor's published plans and documentation, not a hands-on test.

Fit

Is Flagsmith right for your team?

A good fit if…

  • You want to release changes to a small group before everyone
  • You need to self-host for data or compliance reasons
  • You want flags and A/B tests managed in one place
  • You already use an analytics tool to measure user behavior

Look elsewhere if…

  • Marketers need a visual editor to build page tests without developers
  • You want detailed product analytics in the same tool
  • Nobody on the team can add flags to the code

Integrations

Connects with

  • Webhooks

From the vendor's own integrations list.

Support and training

Support
Help center
Training
Blog, Docs
Deployment
Web, Self-hosted

Reviews

What Flagsmith users say

We haven't found published reviews of Flagsmith on G2 or Capterra yet. Smaller lean tools often have none, so judge it on the facts above and a trial.

Similar tools

Flagsmith alternatives

Amplitude

Free plan + paid

Product analytics platform for funnels, retention and cohorts, with built-in experimentation and session replay.

Build-Measure-LearnCohort AnalysisFunnel Metrics

Datadog Experiments (formerly Eppo)

Price on request

Warehouse-native A/B testing and feature-flagging platform, rebranded under Datadog after its 2025 acquisition.

A/B TestingFeature FlagsHypothesis testing

GrowthBook

Free plan + paid

Open-source, warehouse-native experimentation and feature-flag platform with Bayesian and frequentist stats engines.

A/B TestingFeature FlagsHypothesis testing

Optimizely

Price on request

Enterprise digital experience platform offering web and feature experimentation alongside CMS and personalization.

A/B TestingMultivariate TestingFeature Flags
Flagsmith compared with Amplitude, Datadog Experiments (formerly Eppo), GrowthBook, Optimizely
ToolPricingStarting priceFree plan or trialDeployment
FlagsmithFreeFree open-source edition; hosted plan prices not confirmed from search resultsFree planWeb, Self-hosted
AmplitudeFree plan + paidPlus plan announced at $49 per month; check the pricing page for current termsFree planWeb
Datadog Experiments (formerly Eppo)Price on requestQuote-basedNone listedWeb
GrowthBookFree plan + paidFree; Pro $40 per seat/monthFree planWeb, Self-hosted
OptimizelyPrice on requestQuote-basedNone listedWeb

From each vendor's published pricing. Check current prices on their sites.

FAQ

Flagsmith: common questions

What is Flagsmith?
Flagsmith is an open-source feature flag platform with remote config and experimentation, available hosted or self-hosted.
Is Flagsmith open source?
Yes. Its code is published on GitHub, and the vendor has pages on open-source and self-hosted use.
Can Flagsmith run A/B tests?
Yes. Multivariate flags split users between variations, and the docs cover experiments and A/B testing with analytics integrations.
How much does Flagsmith cost?
The open-source edition is free to self-host. Hosted plan prices are on the vendor's pricing page.
Can Flagsmith target groups of users?
Yes. Segments target flags at users by their traits.

For the Flagsmith team

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Sources, checked October 29, 2026

Listed October 29, 2026.