Almost every startup needs a database, and almost every startup starts by asking which hosted Postgres option is free. The good news is that several reputable providers offer a free tier that comfortably handles a side project or an early product. The bad news is that free tiers differ in ways that matter: storage limits, connection limits, sleep behaviour, and what happens when you outgrow them. Comparing those details now saves a painful migration later.

Supabase offers a generous free tier built around Postgres with a generous set of companion tools, including authentication and storage, and it suits teams that want a backend, not just a database. Neon provides serverless Postgres with branching, which lets you create a copy of your database for a feature branch in seconds, and its free tier fits small projects well. Railway gives a simple deploy experience with a monthly usage credit that covers a small database, though you must watch usage to stay free. Render offers a free Postgres tier with a storage cap and an expiry window on the free instance, which makes it better for experiments than for long-lived products. Aiven and similar providers focus on larger plans, but their trial credits can be useful for short evaluations.

Four limits decide whether a free tier fits you. Storage caps matter once your data grows past a few hundred megabytes, which happens faster than expected with logs or user uploads. Connection limits matter for apps with many simultaneous users or poorly pooled connections; a small pooler in front of the database solves most of this. Sleep or pause behaviour matters if your app must respond instantly at any hour, since some free tiers pause after inactivity and take seconds to wake. Backup and retention policies matter the day something goes wrong, and free tiers often keep fewer backups than paid ones.

Staying free is mostly about discipline. Enable connection pooling from day one, keep large files in object storage instead of the database, and set up an alert for usage approaching the cap. Also plan your exit before you need it: use standard Postgres features rather than provider-specific extensions, keep regular logical backups you control, and document the connection settings in one place. A database you can move is a database you can afford to outgrow.

Pay when the free tier costs you more in risk or time than the paid plan costs in money. That moment usually arrives when you have real users depending on the app, when backups and uptime guarantees matter, or when you spend more time nursing limits than building features. A small paid database, often under twenty dollars a month, buys support, better backups, and room to grow. Treat the free tier as a launchpad, not a permanent home, and the upgrade will feel like progress rather than a bill you resent.

Start with the provider whose limits match your project: Supabase or Neon for most small apps, Railway for simple deploys, Render for short experiments. Build with standard Postgres, back up regularly, and watch your usage monthly. The best free database is not the one with the biggest headline numbers. It is the one whose limits you understand, and whose exit you have already planned.

Whatever free tier you choose, keep a backup you control outside that provider. A scheduled logical dump, stored in a different service or on your own machine, protects you against the failure modes a provider's own backups do not cover: an account problem, an accidental deletion, or a free tier that changes its terms. Test restoring that dump into a local database at least once, because a backup that has never been restored is an assumption, and assumptions fail at the worst possible moment.

Also watch for the quiet signals that a free tier is ending. Providers change free plans with notice periods that are easy to miss in a busy inbox, and a database that worked yesterday can start warning about limits tomorrow. Set a monthly reminder to check usage and read provider announcements, and keep your migration notes current: connection strings, extensions used, and the steps to point your app at a new database. Ten minutes a month of attention is the price of staying free without being caught by surprise.