Sizes and limits

What each part gets, and what happens when it reaches the edge.

Applications

Memory: 256 MB, 512 MB (default) or 1 GB, chosen in the project's settings. Above 90% for five minutes you are warned; at the limit the application is restarted.
CPU: 0.25, 0.5 (default) or 1
Own disk: 1 GB, and temporary: it is replaced on every deployment. Over the limit the application is stopped.
Processes: 256
Build: 15 minutes

Data

Postgres: 512 MB of memory, 1 GB of data. Over that it becomes read-only until it shrinks.
Redis: 128 MB. When full, writes fail.
File storage: 1 GB. A write over the quota fails.
Permanent disk: 1 GB, one per project. At the limit the application is stopped; nothing is deleted.

Per account and project

Projects: 20
Branch environments: 5 per project, 3 of them pull request previews
Variables: 100 per project
Background services: 5 per project
Scheduled jobs: 10 per project, at most every 5 minutes
Custom domains: 10 per project
Groups: 10 per account, 10 projects each

When the server is full

The preview runs on one server. A deployment, a bigger size, a database or a Redis is refused with a clear message when there is no memory left to promise, rather than slowing everyone down. The sidebar shows how much room is left.

Sleep when idle

Optional per project, and on by default for branch environments. After 15 minutes without a request the application and its database are stopped and use no memory. The next request starts them again and is held for the few seconds that takes.