🗄️ databases

MongoDB costs $25/mo.
These cost $0.

8 free alternatives to MongoDB, checked for license, recent activity and real adoption. Each one tells you the catch, so you can switch with your eyes open.

⚡ Quick Verdict · 2027 Guide

The top-rated free, open-source replacement for MongoDB is TiDB (Open Source Open Source). Across this category, 2 self-hostable tools are available (including Convex and Memgraph). Switching a 5-person team saves up to $1,500/year compared to MongoDB's $25/mo subscription.

The catch: Community-driven open source project without dedicated enterprise SLAs.

See the 8 picks ↓

MongoDB vs Free Alternatives

Quick side-by-side comparison · $0/mo vs $25/mo

Alternative	Type	License	Where It Runs	Stars	Head-to-Head
TiDB	open source	Open Source	Local	★ 40.7k	MongoDB vs TiDB →
Turso	open source	Open Source	Local	★ 17.3k	MongoDB vs Turso →
Convex	open source	Open Source	Self-host	★ 12.8k	MongoDB vs Convex →
Instant	open source	Open Source	Local	★ 10.6k	MongoDB vs Instant →
OceanBase	open source	Open Source	Local	★ 10.4k	MongoDB vs OceanBase →
Activeloop	open source	Open Source	Local	★ 9.3k	MongoDB vs Activeloop →
Memgraph	open source	Open Source	Self-host	★ 4.7k	MongoDB vs Memgraph →
SlateDB	open source	Open Source	Local	★ 3.6k	MongoDB vs SlateDB →

The picks

8 open source · ranked by fit

01
TiDB
open sourceOpen SourceLocal
40.7knov 2026
Distributed SQL database combining OLTP and OLAP capabilities, offering horizontal scalability, high availability, and real-time analytics.
The catch vs MongoDB
Community-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
Visit tidb.cloud ↗Source Compare vs MongoDB →also replaces 3 other apps →
02
Turso
open sourceOpen SourceLocal
17.3knov 2026
Turso provides a simple developer experience with SQLite compatibility, allowing you to build and scale multi-tenant applications with unlimited databases.
The catch vs MongoDB
Community-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
platforms
desktopcross-platformone-click install
install
Clone https://github.com/tursodatabase/libsql 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
Visit turso.tech ↗Source Compare vs MongoDB →also replaces 5 other apps →
03
Convex
open sourceOpen SourceSelf-host
12.8knov 2026
Open-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 MongoDB
Requires self-hosting setup, updates, and server maintenance compared to managed MongoDB.
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
Visit convex.dev ↗Source Compare vs MongoDB →also replaces 4 other apps →
04
Instant
open sourceOpen SourceLocal
10.6knov 2026
Instant is a database solution for building real-time and offline-enabled applications, simplifying the development of collaborative products.
The catch vs MongoDB
Community-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
Visit instantdb.com ↗Source Compare vs MongoDB →also replaces 4 other apps →
05
OceanBase
open sourceOpen SourceLocal
10.4knov 2026
Scalable, high-availability database system supporting OLTP, OLAP, and hybrid transactional/analytical processing workloads.
The catch vs MongoDB
Community-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
Visit en.oceanbase.com ↗Source Compare vs MongoDB →also replaces 4 other apps →
06
Activeloop
open sourceOpen SourceLocal
9.3knov 2026
Deep Lake is an open-source database for storing, querying and managing complex AI data like images, audio, and embeddings.
The catch vs MongoDB
Community-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
platforms
desktopcross-platformone-click install
install
Clone https://github.com/activeloopai/deeplake 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
Visit activeloop.ai ↗Source Compare vs MongoDB →also replaces 3 other apps →
07
Memgraph
open sourceOpen SourceSelf-host
4.7knov 2026
Memgraph is a scalable, in-memory graph database solution offering high-performance computing and Neo4j compatibility.
The catch vs MongoDB
Requires self-hosting setup, updates, and server maintenance compared to managed Neo4j AuraDB.
Install, platforms & data +
platforms
webself-hosteddocker to self-host
install
Clone https://github.com/memgraph/memgraph 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
Visit memgraph.com ↗Source Compare vs MongoDB →also replaces 3 other apps →
08
SlateDB
open sourceOpen SourceLocal
3.6knov 2026
SlateDB is an embedded storage engine that leverages object storage for durability, scalability, and simplified replication without the need for disk management.
The catch vs MongoDB
Community-driven open source project without dedicated enterprise SLAs.
Install, platforms & data +
platforms
desktopcross-platformone-click install
install
Clone https://github.com/slatedb/slatedb 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
Visit slatedb.io ↗Source Compare vs MongoDB →also replaces 6 other apps →

MongoDB Head-to-Head Comparisons (2027)

Side-by-side trade-off breakdowns · 8 free alternatives

MongoDB vs TiDBOpen Source · Local →

MongoDB vs TursoOpen Source · Local →

MongoDB vs ConvexOpen Source · Self-host →

MongoDB vs InstantOpen Source · Local →

MongoDB vs OceanBaseOpen Source · Local →

MongoDB vs ActiveloopOpen Source · Local →

MongoDB vs MemgraphOpen Source · Self-host →

MongoDB vs SlateDBOpen Source · Local →

Frequently Asked Questions

Direct answers · MongoDB open-source replacements

What is the best free alternative to MongoDB?+

The top free alternative to MongoDB is TiDB (open source, Open Source). Distributed SQL database combining OLTP and OLAP capabilities, offering horizontal scalability, high availability, and real-time analytics. Other popular MongoDB replacements include Turso, Convex, Instant.

Can I self-host a free replacement for MongoDB?+

Yes. Of the 8 free alternatives to MongoDB, 2 can be self-hosted on your own server or local machine: Convex (Open Source), Memgraph (Open Source).

How much does switching from MongoDB to a free alternative save?+

MongoDB starts at $25/month per seat ($300/year). Switching a 5-person team to a free alternative like TiDB saves $1,500 per year in software subscription fees.

Should I vibe-code or build my own MongoDB clone from scratch?+

Our build verdict for MongoDB is NO (use a free alternative, save the tokens). Instead of paying recurring SaaS fees for MongoDB or rebuilding it from scratch, deploy one of the 8 battle-tested open-source alternatives like TiDB.

What is the catch when switching from MongoDB to TiDB?+

Community-driven open source project without dedicated enterprise SLAs.