The best backend as a service platforms in 2026

Supabase gives you a full Postgres database per project, plus authentication, file storage, realtime subscriptions and edge functions. Because the data sits in plain Postgres, you can query it with SQL, connect any Postgres tool, and take a dump with you if you leave. For AI apps, the pgvector extension stores embeddings and runs similarity search in the same database. Our full Supabase review goes through each plan, and the Pinecone vs Supabase comparison covers its vector search for AI apps.

The free plan allows 2 active projects, 500 MB of database per project and 50,000 monthly active users. Free projects are paused after 1 week of inactivity, which catches many people with a demo they forgot about. Pro starts at $25 a month with the first project included; each extra project adds compute from $10 a month. Spend caps are on by default on Pro, so a traffic spike cannot turn into an open-ended bill unless you switch the cap off.

The limit: Row Level Security policies are how you protect data that the browser reads directly, and writing them is the real learning curve. Skip them and your tables are exposed.

Firebase is Google's app platform: Firestore (a NoSQL document database with offline sync on mobile), Authentication, Cloud Functions, Cloud Storage, Hosting, Crashlytics and Cloud Messaging for push notifications. Its mobile SDKs cover offline persistence and push out of the box, which is why so many iOS and Android apps start on it. For AI features, Firestore also runs K-nearest neighbor vector queries. If you are already thinking of leaving, our guide to switching from Firebase covers the move.

The Spark plan costs nothing and needs no payment method. Firestore on Spark includes 1 GiB stored, 50K reads and 20K writes a day; Authentication is free up to 50K monthly active users. Blaze is pay as you go, with $300 of Google Cloud credit for eligible new accounts.

The limit is the bill. Firestore charges per document read, so a badly written listener can read the same collection thousands of times. Budget alerts do not pause services; Firebase now offers spend caps that pause a service at 100% of its budget, but only for four services (AI Logic, App Hosting, Cloud Functions and Extensions), and the cut is not instant.

Xano is the backend for people who don't want to write backend code. You design a Postgres database, then build API endpoints with a visual function stack: queries, conditions, loops, external API calls, authentication. Front-end builders like FlutterFlow, WeWeb or Bubble then call those APIs, and the MCP builder turns them into tools an AI agent can call. Our Xano review details each plan and the Bubble vs Xano comparison explains when to split front end and backend.

The Free plan is for building: it is limited to 10 API requests per 20 seconds and up to 100K records, so it cannot carry real traffic. Essential costs $85 a month billed annually, or $99 billed monthly; Pro is $224 billed annually, or $249 monthly. Paid plans have no API rate limit, on a flat monthly fee. Leaving is possible: the data sits in standard Postgres and exports directly, and the logic is readable as XanoScript, though it has to be translated to run anywhere else.

The limit: you still think like a developer (variables, loops, tokens), and the jump from free to $85 a month is steep for a side project.

Appwrite bundles auth, databases, storage, functions, messaging and site hosting in one open source project. You can run it on Appwrite Cloud or on your own server with Docker, and its SDKs cover web, Flutter, Apple, Android and many server languages.

Free organizations are 100% free on Appwrite Cloud, with 2 projects that pause after 1 week of inactivity. At a free limit, your project freezes and the console goes read-only until you upgrade or remove resources. Pro costs from $25 a month for one project, plus $15 for each additional project, with usage beyond the included resources billed on top and an optional budget cap. Databases can now run on serverless compute (the default, TablesDB) or on dedicated tiers from $10 a month per database, which is where PostgreSQL and MySQL are offered. For AI, VectorsDB stores embeddings and runs similarity search, with built-in text embeddings (1M tokens a month on Free, 10M on Pro).

The limit: its default database is not plain Postgres like Supabase's (Postgres means paying for a dedicated tier), and fewer third-party tutorials exist than for Firebase or Supabase.

Convex is a reactive backend: you write queries and mutations as TypeScript functions, and every client subscribed to a query gets the new result as soon as the data changes. No cache to invalidate and no websocket code to write. It is popular for chat, dashboards, multiplayer tools and AI apps, and vector indexes add similarity search, run from Convex actions.

The Free & Starter plan covers 1 to 6 developers and includes 1M function calls, then $2.20 per additional million. Professional costs $25 per developer per month, and the Business plan has a $2,500 monthly minimum. Watch the region: usage outside the US region (Ireland, Sydney, Canada) is billed at 1.3 times the standard rate, so keep US East unless your data has to stay in Europe.

The limit: your backend logic lives in Convex's own model, so moving away means rewriting more than with a Postgres-based service.

PocketBase is an open source backend in one file: an embedded SQLite database with a schema builder, realtime subscriptions, authentication, file storage and an admin dashboard. You download it, run it on a small VPS, and you have a backend. It is under the MIT license and costs nothing beyond your server. Custom logic, AI calls included, goes in Go or JavaScript hooks.

It scales only on a single server, vertically, which is plenty for most side projects and internal tools. The project warns that full backward compatibility is not guaranteed before reaching v1.0.0, so read the changelog before each upgrade.

The limit: it runs on one server, and you own backups, updates and security.

Back4App hosts Parse Server, the open source backend that Facebook released after closing Parse. You get a database with REST and GraphQL APIs, cloud code functions, authentication, files and push notifications, plus an AI agent that builds an app from a description and an MCP server that lets an IDE agent create databases, APIs and cloud functions (MCP access itself is free). Because Parse is open source, you can move your app to your own Parse Server later.

The free plan is meant for developing, learning and prototyping: 25K requests a month, 250 MB of data storage and 1 GB of transfer. Paid plans are priced per app and per month, billed annually: MVP at $15 (500K requests), Pay As You Go at $80 (5M requests) and Dedicated at $400. Billed monthly, MVP costs $25, so the annual price only pays off once the app is here to stay. Watch data storage: past your plan's threshold, each extra gigabyte costs $15 a month, while file storage costs $1 per 10 GB.

The limit: plans are capped by request counts, so a busy app climbs plans quickly, and the Parse community is smaller than in its early days.

Nhost pairs a Postgres database with Hasura, which generates a GraphQL API from your tables, and adds authentication, storage and serverless functions. If your front end is built around GraphQL, it saves you writing resolvers. Nhost is open source, so you can self-host it.

The free Starter plan allows 1 project with a 1 GB database, and the project is paused after 1 week of inactivity. Pro starts at $25 a month, with $15 of compute credits included, a 10 GB database (then $0.20 per GB) and 50 GB of egress. pgvector comes in its AI toolkit. Two costs to plan for: a custom domain is $10 per project a month, and the next plan, Team, starts at $599 a month.

The limit: if you don't want GraphQL, Supabase covers the same ground with a larger ecosystem.