Find your next tool.
Find tools for your next project. Start with free options. Know the limits before you commit.
Free options first. Paid tools when you need more.
Supabase
Free plan · Add a database, login, and storage to your app.
500 MB database, 1 GB file storage, 50,000 MAUs, 2 active projects
Pricing checked Oct 2026 · Compare plans and costs
Ably
Free plan · Reliable pub/sub with guaranteed message ordering and offline catch-up
Free plan: 6M messages/month, 200 concurrent connections
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BetterUptime
Free plan · Uptime monitoring with on-call alerts
Free: 10 monitors & heartbeats, 1 status page, Slack/email alerts
Pricing checked Oct 2026 · Compare plans and costs
Expo
Free plan · Build and deploy React Native apps to iOS and Android from one codebase
Free plan: 15 Android + 15 iOS builds/mo, updates to 1K MAUs, 60 CI/CD minutes
Pricing checked Oct 2026 · Compare plans and costs
Express Rate Limit
Free · Drop-in rate limiting middleware for Express apps with flexible storage backends
Free and open source (MIT license)
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Firebase Cloud Messaging
Free plan · Google's free push delivery backbone used by millions of apps worldwide
FCM is available at no charge on Firebase plans; service quotas still apply.
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Flagsmith
Free plan · Feature flags and remote configuration with both cloud and self-hosted options
Free hosted plan: 50,000 API requests/month, one team member and one project; fair-use limits apply.
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GitHub
Free plan · Store code and work on it together.
Free plan: unlimited public/private repos, 2,000 CI/CD minutes/month
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GitHub Actions
Free plan · Run tests and build checks on every pull request
Standard GitHub-hosted runners are free for public repositories; self-hosted runners are free. Private-repository allowances depend on the account or organization plan.
Pricing checked Oct 2026 · Compare plans and costs
Google Calendar API
Free plan · Build a fully custom scheduling experience backed by Google Calendar availability
Standard usage currently has no additional charge; quotas and a published daily billing threshold apply.
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LaunchDarkly
Free plan · Industry-standard feature flag platform with targeting, experimentation, and audit logs
Developer plan: $0, unlimited seats, 1 project/3 environments, 5K AI runs/mo
Pricing checked Oct 2026 · Compare plans and costs
OneSignal
Free plan · Send targeted push notifications to iOS and Android users
Free: mobile push for organizations up to 1,000 MAUs; 10,000 email sends/month; web push limited to 10,000 subscribers per send.
Pricing checked Oct 2026 · Compare plans and costs
Postman
Free plan · Test endpoints and auto-generate collections from your API
Free plan: 1 user, API client, mock servers, 1K monitoring requests/mo
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Pusher
Free plan · Managed WebSocket infrastructure that handles connections, scaling, and presence
Sandbox: free forever — 100 concurrent connections, 200K messages/day
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Pusher Beams
Free plan · Managed push notifications with per-device delivery receipts and analytics
Sandbox: free — up to 1,000 subscribed devices, unlimited notifications
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ReadMe
Free plan · Host polished, versioned docs with a built-in API explorer
Starter plan free: 1 project, 1 version, custom domain, interactive API reference
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Sentry
Free plan · Real-time error tracking and stack traces
Developer plan: 1 user, 5K errors, 5M spans, 50 replays, 5 GB logs
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Socket.io
Free · Full-featured WebSocket library with automatic fallback and room-based messaging
Free and open source (MIT license)
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Supabase Auth
Free plan · Built-in auth with social providers
Included in every Supabase plan — Free tier covers 50,000 MAUs
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Supabase Realtime
Free plan · Subscribe to Postgres table changes and broadcast them to connected clients instantly
Included in every Supabase plan with message/connection quotas
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Swagger UI
Free · Render an OpenAPI spec as browsable, try-it-now documentation
Free and open source (Apache 2.0)
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Unleash
Free · self-hosted · Open-source feature toggle service you can host on your own infrastructure
The software is free to self-host. Hosting and maintenance may cost extra.
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Upstash
Free plan · Serverless Redis with a per-request pricing model ideal for rate limiting counters
Free Redis database: 500,000 commands/month, 10 GB bandwidth and 250 MB advertised data allowance.
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Vercel AI SDK
Free · Stream AI responses to your frontend
Free and open source (Apache 2.0)
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Web Push API
Free · Browser-native push standard that works without a third-party service
Free web standard built into browsers
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Zod
Free · Validate form inputs client and server side
Free and open source (MIT license)
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Kong
Free trial · Open-source API gateway with built-in rate limiting, auth, and routing plugins
No perpetual free Konnect plan advertised; 30-day trial, no card required.
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OpenAI
Paid · Add AI features to your app with an API.
API usage is billed separately from ChatGPT subscriptions; any promotional credits are not a permanent free API tier.
Pricing checked Oct 2026 · Compare plans and costs
Twilio Verify
Free trial · Send one-time passcodes via SMS or voice call with global delivery
No free tier — free trial available
Pricing checked Oct 2026 · Compare plans and costs
Free plans have limits. Pricing can change; check the provider before signing up.