A Platform as a Service runs your whole application — code, dependencies and a database — from a Git push, without you managing servers or containers.
Platform as a Service sits between raw servers and serverless functions: you push code, and the platform builds it, runs it, connects a database and gives you a URL — but unlike serverless, your app runs as a continuous process. That makes PaaS the natural home for full-stack apps, APIs with persistent connections, background workers and anything built on a framework that expects to stay running.
The defining trade-off on free PaaS tiers is how the provider keeps them affordable. Some idle your app after a period of no traffic and wake it on the next request, trading a cold-start delay for free always-available hosting; others give you a fixed monthly credit that depletes as the app runs. Railway and Render are common picks, and the right one depends on whether your project tolerates sleeping and how its resource usage maps to each platform’s allowance.
When comparing options, check four things: whether the free tier is perpetual or a depleting trial, the sleep/idle policy, what database and persistent storage are included, and the supported runtimes (including Dockerfile support if you need it). A PaaS that bundles a managed Postgres on the same free account saves you from wiring up a separate database provider, which is often the difference between a five-minute deploy and an afternoon of setup.
Railway Railway Corp Railway is an infrastructure platform where you can provision infrastructure, develop with it locally, and then deploy to the cloud.
Free tier
$5 credit/month, 500 hours execution
Paid from $5/mo · 4 regions
Render Render Services Inc. Render is a unified cloud to build and run all your apps and websites with free TLS certificates, a global CDN, private networks and auto deploys from Git.
Free tier
750 hours/month for web services
Paid from $7/mo · 4 regions
To keep free tiers sustainable, some PaaS providers idle apps that receive no traffic and wake them on the next request, which adds a startup delay. Check each platform's policy if you need an always-on service — it's a common reason people upgrade.
Pick a PaaS for long-running apps, persistent connections (like WebSockets) and frameworks that expect a continuous process. Pick serverless for short, spiky, event-driven workloads. PaaS is closer to a traditional server experience with the ops removed.
It varies. Some platforms offer a perpetual free allowance; others give monthly trial credits that run out. Read the fine print so a 'free' deploy doesn't unexpectedly start billing.