SignaKit vs GrowthBook
GrowthBook and SignaKit both cover feature flags and A/B testing, but they're built for different teams. GrowthBook is designed for data-mature organizations with an existing warehouse. SignaKit is designed for engineering teams who want flags, experimentation, and analytics without setting up any data infrastructure.
Last updated May 2026. Pricing and feature data verified from public sources.
Quick verdict
| SignaKit | GrowthBook | |
|---|---|---|
| Best for | Engineering teams: flags + experimentation, no infra required | Data teams: warehouse-native experiments + open source |
| Pricing model | Event-based flat rate (flag evaluations free) | Per-seat ($40/seat/mo on Pro) |
| Free cloud tier | ✓1M events/mo, 5 members | ✓3 members, CDN-limited |
| Free unlimited tier | No self-hosting | ✓Self-hosted open source |
| Built-in event collection | ✓ | Requires external warehouse |
| Warehouse required | Not needed | Required for analytics |
| Multi-armed bandit | ✓All plans | Pro only ($40/seat/mo) |
| A/B testing | ✓All plans | ✓All plans |
| Managed cloud | ✓ | Limited on free tier |
| SDK count | 11 | 24+ |
Feature comparison
Core feature flags
| SignaKit | GrowthBook | |
|---|---|---|
| Boolean flags | ✓ | ✓ |
| Multivariate flags | ✓ | ✓ |
| User/segment targeting | ✓ | ✓ |
| Percentage rollouts | ✓ | ✓ |
| Kill switches | ✓ | ✓ |
| Dark launches | ✓ | ✓ |
| Flag lifecycle management | ✓ | ✓ |
| Flag audit log | ✓ | ✓ |
| Prerequisite flags | — | Enterprise only |
| Approval workflows | — | Enterprise only |
| Visual A/B editor | — | Pro only |
Experimentation & analytics
| SignaKit | GrowthBook | |
|---|---|---|
| A/B testing | ✓All plans | ✓All plans |
| Multivariate testing | ✓ | ✓ |
| Multi-armed bandit | ✓All plans | Pro only |
| Statistical significance (z-test) | ✓ | ✓ |
| Confidence intervals | ✓ | ✓ |
| Experiment snapshots | ✓ | ✓ |
| CUPED variance reduction | — | Pro only |
| Sequential testing | — | Pro only |
| Custom event tracking | ✓Built-in | Bring your own warehouse |
| Conversion attribution | ✓ | ✓With warehouse |
| Slack experiment alerts | ✓Starter+ | ✕ |
Developer experience
| SignaKit | GrowthBook | |
|---|---|---|
| Node.js SDK | ✓ | ✓ |
| React SDK | ✓ | ✓ |
| React Native SDK | ✓ | ✓ |
| Next.js SDK | ✓ | ✓ |
| PHP / Laravel SDK | ✓ | ✓PHP (no Laravel) |
| Python SDK | ✓ | ✓ |
| Go SDK | ✓ | ✓ |
| Ruby SDK | ✓ | ✓ |
| Swift / Kotlin SDK | — | ✓ |
| Rust SDK | — | ✓ |
| Elixir / Flutter SDK | — | ✓ |
| Total native SDKs | 11 | 24+ |
| Local flag evaluation (no network call) | ✓ | ✓ |
| REST API | ✓ | ✓ |
| MCP / IDE integration | — | ✓ |
Infrastructure & security
| SignaKit | GrowthBook | |
|---|---|---|
| Managed cloud | ✓ | Limited free tier |
| Self-hosted / open source | — | ✓ |
| Role-based access control | ✓ | ✓ |
| SSO/SAML | Planned | Enterprise only |
| Approval workflows | — | Enterprise only |
| Audit logs | ✓ | Enterprise only |
| Slack + email notifications | ✓Starter+ | ✕ |
| Data residency / self-hosting | — | ✓ |
| CDN-delivered flags | ✓ | Limits on cloud plans |
⚠ = restricted to a higher tier or paid add-on · — = not yet available
Pricing comparison
GrowthBook
As of May 2026
| Plan | Price | Limits |
|---|---|---|
| Open Source | Free | Self-hosted, unlimited |
| Starter (cloud) | Free | 3 seats, 1M CDN req/mo |
| Pro (cloud) | $40/seat/mo | 2M CDN req/mo, up to 50 seats |
| Enterprise | Custom | Custom limits |
Watch for seat-based scaling: At $40/seat/mo, a 10-person team pays $4,800/year. CDN request overages add $10/M requests above the plan limit. MAB and advanced stats require Pro.
SignaKit
As of May 2026
| Plan | Monthly | Events/mo | Members |
|---|---|---|---|
| Free | $0 | 1M | 5 |
| Starter | $39 | 5M | 15 |
| Growth | $119 | 25M | 30 |
| Enterprise | Contact | Unlimited | Unlimited |
Flag evaluations are always free. They run locally in the SDK — no network call, no billing. Only exposure events (once per user per flag per session) and custom metric events count. Overage is $3 per 1M events.
Where each platform wins
GrowthBook wins
Warehouse-native experiments
If you already have Snowflake, BigQuery, or Redshift, GrowthBook's architecture eliminates metrics double-counting and gives your data team full SQL control over experiment definitions. No separate event pipeline to maintain.
Open source and self-hostable
GrowthBook is fully open source. Teams with data residency requirements or a preference for self-managed infrastructure can run unlimited flags and experiments at zero licensing cost.
Advanced statistical methods
CUPED variance reduction, sequential testing, and multi-metric analysis are available on Pro. For data-science-led organizations running high volumes of concurrent experiments, these are genuine advantages.
SDK breadth
24+ native SDKs covers Rust, Swift, Kotlin, Elixir, Flutter, and Cloudflare Workers — languages SignaKit does not yet support.
SignaKit wins
No warehouse, no problem
SignaKit collects and stores its own events — no external data pipeline or warehouse required. Teams that don't have a warehouse (or don't want the overhead of managing one) are fully supported out of the box.
Multi-armed bandit on all plans
SignaKit automatically shifts traffic toward the winning variation using Thompson Sampling. GrowthBook gates multi-armed bandit behind its Pro plan ($40/seat/mo). SignaKit includes it on the free tier.
Predictable flat-rate pricing
GrowthBook Pro at $40/seat/mo means a 10-person team pays $4,800/year before CDN overages. SignaKit charges by events — a 10-person team and a 50-person team running the same traffic pay the same.
Slack experiment alerts
SignaKit sends Slack notifications when experiments reach statistical significance and when flags change. GrowthBook does not include Slack alerting on any cloud plan.
Who should choose which
Choose GrowthBook if…
- You already have a data warehouse (Snowflake, BigQuery, Redshift, Databricks) and want to run experiments against it
- Your data team owns experiment analysis and prefers SQL-defined metrics over opaque event collection
- You need self-hosting for compliance, data residency, or cost reasons
- You need SDK coverage for Rust, Swift, Kotlin, Elixir, or Flutter
- You need CUPED or sequential testing for high-volume concurrent experiments
Choose SignaKit if…
- You don't have a data warehouse and don't want to set one up just to run experiments
- You want feature flags, A/B testing, multi-armed bandit, and event analytics under one roof — managed, no ops burden
- Your team is growing and you don't want a per-seat bill that scales against you
- You want Slack alerts when experiments reach significance without paying enterprise prices
- You're building on Node, React, Next.js, PHP, Python, Go, Ruby, or Laravel
Switching from GrowthBook to SignaKit
Both platforms use local SDK evaluation, so migration is low-risk. You can run them in parallel and transition at your own pace.
Install the SignaKit SDK alongside GrowthBook
Both SDKs can coexist in your codebase. No forced cutover, no downtime.
Instrument SignaKit events for your key metrics
Replace GrowthBook's warehouse-routed metric events with SignaKit's built-in track() calls. This typically takes a few hours for a standard set of conversion events.
Migrate flags environment by environment
Move dev → staging → production at your own pace. Recreate your flags in SignaKit and shadow-evaluate both during the transition period.
Remove the GrowthBook SDK
Once all flags and experiments are live in SignaKit, remove the old SDK. Most teams complete a full migration in 1–3 weeks.
Frequently asked questions
Do I need a data warehouse to use GrowthBook?
GrowthBook's experimentation analytics layer is warehouse-native — you connect your Snowflake, BigQuery, or Redshift instance and run experiment analysis against your own event data. Feature flags work without a warehouse, but the analytics side requires one. SignaKit includes its own event collection layer, so no external warehouse is needed.
Is GrowthBook actually free?
GrowthBook's most generous free tier is the self-hosted open-source version, which is unlimited but requires you to run and maintain your own infrastructure. The free managed cloud tier is limited to 3 seats and has CDN request caps. SignaKit's free cloud tier includes 1M events/month and 5 members with no infrastructure to manage.
Does SignaKit have a free tier?
Yes — up to 1M events/month, 1 project, and 5 members. No credit card required. Flag evaluations happen inside the SDK and are always free regardless of plan.
Do flag evaluations count toward my event limit?
No. Flag evaluations run entirely inside the SDK — no network call is made per evaluation. Only exposure events (once per user per flag per session) and custom metric events count toward the monthly limit.
GrowthBook has 24+ SDKs — what does SignaKit cover?
SignaKit has 11 SDKs: JavaScript, TypeScript, React, React Native, Node.js, Python, Go, Ruby, PHP, Laravel, and Java. GrowthBook covers more niche languages (Rust, Swift, Kotlin, Elixir, Flutter). If your stack is covered by SignaKit, you get the same local SDK evaluation model with built-in event tracking.
Is GrowthBook better for experimentation statistics?
GrowthBook Pro includes CUPED variance reduction and sequential testing — advanced techniques that are genuinely valuable at scale. SignaKit provides frequentist A/B testing with z-tests, confidence intervals, and statistical significance on all plans. For most product teams, SignaKit's statistics are more than sufficient; for data-science-led teams running hundreds of concurrent experiments, GrowthBook's advanced stats are a real advantage.
Can I switch from GrowthBook to SignaKit?
Yes. You can run both SDKs in parallel during the transition. Migrate flag by flag, environment by environment. Most teams complete a full migration in 2–4 weeks.
Start free. No credit card required.
Free forever on the first million events. A/B testing and multi-armed bandit included on all plans. No warehouse needed.