Fauna costs $25/mo.
These cost $0.
5 free alternatives to Fauna, checked for license, recent activity and real adoption. Each one tells you the catch, so you can switch with your eyes open.
The top-rated free, open-source replacement for Fauna is Supabase (Apache-2.0 Open Source). Across this category, 2 self-hostable tools are available (including Supabase and Convex). Switching a 5-person team saves up to $1,500/year compared to Fauna's $25/mo subscription.
The catch: Supabase replaces Convex's document/function runtime with PostgreSQL, SQL migrations, row-level security, and separate services, so the application architecture must be rewritten rather than simply moved.
Fauna vs Free Alternatives
Quick side-by-side comparison · $0/mo vs $25/mo
| Alternative | Type | License | Where It Runs | Stars | Head-to-Head |
|---|---|---|---|---|---|
| Supabase | open source | Apache-2.0 | Self-host | ★ 114.6k | Fauna vs Supabase → |
| TiDB | open source | Open Source | Local | ★ 40.7k | Fauna vs TiDB → |
| Convex | open source | Open Source | Self-host | ★ 12.8k | Fauna vs Convex → |
| Instant | open source | Open Source | Local | ★ 10.6k | Fauna vs Instant → |
| OceanBase | open source | Open Source | Local | ★ 10.4k | Fauna vs OceanBase → |
The picks
5 open source · ranked by fit
- 01
Supabase
open sourceApache-2.0Self-host114.6knov 2026Provides a full backend stack built on Postgres: authentication, auto-generated APIs, edge functions, realtime subscriptions, file storage, and vector search.
The catch vs FaunaSupabase replaces Convex's document/function runtime with PostgreSQL, SQL migrations, row-level security, and separate services, so the application architecture must be rewritten rather than simply moved.
Install, platforms & data +
- platforms
- webself-hostedcliself-host, real ops
- install
- Hosted Supabase project, or the official Docker Compose stack; `supabase start` runs the local stack
- setup
- Self-hosting is not 'just Postgres': the Compose stack needs many secrets and services, plus SMTP, object storage, TLS, backups, observability, and coordinated upgrades.
- your data
- Relational data, auth records, and platform metadata live in PostgreSQL; Realtime consumes the Postgres replication stream; object data lives in the configured storage backend with metadata in Postgres; edge-function and migration source stays in project files. Supabase Cloud stores and operates the managed copy.
- checked
- 2026-11-07
- 02
TiDB
open sourceOpen SourceLocal40.7knov 2026Distributed SQL database combining OLTP and OLAP capabilities, offering horizontal scalability, high availability, and real-time analytics.
The catch vs FaunaCommunity-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
- platforms
- desktopcross-platformone-click install
- install
- Clone https://github.com/pingcap/tidb or deploy with Docker Compose
- setup
- Download the native package or installer for your operating system.
- your data
- All application data lives locally on your own machine.
- checked
- 2026-11-07
- 03
Convex
open sourceOpen SourceSelf-host12.8knov 2026Open-source reactive database that keeps your web and mobile apps in sync. Write everything in TypeScript with built-in auth, cron jobs, and AI integration.
The catch vs FaunaRequires self-hosting setup, updates, and server maintenance compared to managed Fauna.
Install, platforms & data +
- platforms
- webself-hosteddocker to self-host
- install
- Clone https://github.com/get-convex/convex-backend or deploy with Docker Compose
- setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- your data
- All application data and configuration live on your own server or local database.
- checked
- 2026-11-07
- 04
Instant
open sourceOpen SourceLocal10.6knov 2026Instant is a database solution for building real-time and offline-enabled applications, simplifying the development of collaborative products.
The catch vs FaunaCommunity-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
- platforms
- desktopcross-platformone-click install
- install
- Clone https://github.com/instantdb/instant or deploy with Docker Compose
- setup
- Download the native package or installer for your operating system.
- your data
- All application data lives locally on your own machine.
- checked
- 2026-11-07
- 05
OceanBase
open sourceOpen SourceLocal10.4knov 2026Scalable, high-availability database system supporting OLTP, OLAP, and hybrid transactional/analytical processing workloads.
The catch vs FaunaCommunity-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
- platforms
- desktopcross-platformone-click install
- install
- Clone https://github.com/oceanbase/oceanbase or deploy with Docker Compose
- setup
- Download the native package or installer for your operating system.
- your data
- All application data lives locally on your own machine.
- checked
- 2026-11-07
Fauna Head-to-Head Comparisons (2027)
Side-by-side trade-off breakdowns · 5 free alternatives
Frequently Asked Questions
Direct answers · Fauna open-source replacements
What is the best free alternative to Fauna?+
The top free alternative to Fauna is Supabase (open source, Apache-2.0). Provides a full backend stack built on Postgres: authentication, auto-generated APIs, edge functions, realtime subscriptions, file storage, and vector search. Other popular Fauna replacements include TiDB, Convex, Instant.
Can I self-host a free replacement for Fauna?+
Yes. Of the 5 free alternatives to Fauna, 2 can be self-hosted on your own server or local machine: Supabase (Apache-2.0), Convex (Open Source).
How much does switching from Fauna to a free alternative save?+
Fauna starts at $25/month per seat ($300/year). Switching a 5-person team to a free alternative like Supabase saves $1,500 per year in software subscription fees.
Should I vibe-code or build my own Fauna clone from scratch?+
Our build verdict for Fauna is NO (use a free alternative, save the tokens). Instead of paying recurring SaaS fees for Fauna or rebuilding it from scratch, deploy one of the 5 battle-tested open-source alternatives like Supabase.
What is the catch when switching from Fauna to Supabase?+
Supabase replaces Convex's document/function runtime with PostgreSQL, SQL migrations, row-level security, and separate services, so the application architecture must be rewritten rather than simply moved.
