# Concurrency and queueing

> How many jobs run at once on your plans, what happens to a job that doesn't fit, and where you see the queue.

A plan limits how many jobs run at once and how big each is. It doesn't limit minutes.

## How many jobs run at once

Each plan adds vCPU to your account. Your jobs run at once while they fit in the vCPU of all your plans added together:

| Plan | Per month | vCPU | Largest job | Runs at once |
|---|---|---|---|---|
| S | $39 | 4 | `skipbox` | 1 job at a time on 4 vCPU · 8 GB |
| M | $79 | 8 | `skipbox-8x16` | 1 job at a time on 8 vCPU · 16 GB<br>2 jobs at a time on 4 vCPU · 8 GB |
| L | $149 | 16 | `skipbox-16x32` | 1 job at a time on 16 vCPU · 32 GB<br>2 jobs at a time on 8 vCPU · 16 GB<br>4 jobs at a time on 4 vCPU · 8 GB |

You can hold any number of plans in any mix. Two S plans run two `skipbox` jobs at once. A job's size can't be larger than your largest plan's: see [Labels and sizes](https://docs.skipbox.dev/labels).

The trial runs 1 job at a time, of 4 vCPU.

## A job that doesn't fit

It waits in your account's queue until a running job ends, then starts. Waiting adds nothing to your bill. Your account's page on skipbox.dev shows how many jobs are waiting and how long the oldest has waited, and what to add to run more at once.

A job can also wait when Skipbox's servers are full. Trial jobs can wait longer than paid jobs then.

## How long a job can wait

GitHub cancels a job that has been queued for 24 hours without a runner. Re-run it on GitHub.

## Run more at once

Add plans from your account's page. The added plans are charged at once for the rest of the current month, and jobs waiting start as soon as the payment goes through. See [Plans](https://docs.skipbox.dev/plans).

Updated 2026-11-09 · https://docs.skipbox.dev/concurrency