BuildJet vs GitHub-Hosted Runners: Is It Still Half Price?

By Daniel Zoghalchali·Latchkey

BuildJet lists Linux 2 vCPU at $0.004/min against GitHub-hosted list of $0.006/min. That is 33% cheaper, not the 50% the marketing still claims - GitHub cut its price and the claim did not follow.

BuildJet is one of the longest-running drop-in replacements for GitHub-hosted runners: install the app, change runs-on, and jobs execute on BuildJet hardware. The marketing line is that usage price is half the price of GitHub Actions.

That claim is now out of date, and it is worth being precise about why, because the same staleness affects several competitors. It was accurate when GitHub listed Linux 2-core at $0.008/min. GitHub has since cut the standard Linux 2-core x64 rate to $0.006/min. Against $0.006, BuildJet at $0.004 is 33% cheaper. Still a real saving, just not the advertised one.

And the usual precondition: standard GitHub-hosted runners are free and unlimited on public repositories, at 4 vCPU and 16 GB. Everything below assumes a private repository. Figures verified 2026-08-20.

Published Linux rates, private repository

The saving, stated accurately

BuildJet undercuts GitHub-hosted list at every published Linux size. The margin is a consistent 33% at the low end and widens at 32 vCPU, where BuildJet AMD at $0.048 sits 41% under GitHub-hosted at $0.082.

Watch the ARM memory ratio

The ARM and AMD columns are priced identically but are not equivalent machines. BuildJet ARM ships substantially less RAM at every size, so the same price buys a materially smaller box.

• 2 vCPU: 8 GB on AMD against 3 GB on ARM, at the same $0.004/min.
• 8 vCPU: 32 GB on AMD against 12 GB on ARM, at the same $0.016/min.
• If a job is memory-bound rather than CPU-bound, the ARM option at the same price can be slower or fail outright on out-of-memory.

Concurrency and cache

• Default concurrency is 64 AMD vCPUs and 32 ARM vCPUs. A wide matrix can hit that ceiling and queue.
• Concurrency extensions add 100 vCPUs for $300/month, which is a real cost to fold into any comparison at scale.
• Cache storage is 20 GB per repository weekly, against the 10 GB per-repository limit on GitHub-hosted, with oldest entries cleared automatically.
• Accounts get a one-time $5 credit rather than a recurring free-minute allowance, so unlike Blacksmith at 3,000 free minutes per month there is no ongoing free tier.

Switching, and switching back

One line each way, per job. Point the most expensive job at BuildJet, compare two weeks of real runs, and expand only if the numbers survive contact with your actual pipeline.

jobs:
  build:
    # GitHub-hosted
    runs-on: ubuntu-latest

    # BuildJet
    runs-on: buildjet-4vcpu-ubuntu-2204

    # Latchkey
    runs-on: latchkey-small

What a cheaper minute does not fix

BuildJet lowers the price of a minute. It does not change how many minutes you burn on failures that have nothing to do with your code. A registry timeout, a browser binary that did not install, a transient dependency resolution error: the job fails, the failed minutes are billed, the re-run is billed, and the pipeline waits for a human. A 33% cheaper minute applied to a pipeline that re-runs 10% of its jobs is still paying for those re-runs, just at a discount.

Decide with your own repository

• Both tools in a mature category can do the job. What differs is behaviour on your codebase, which takes an afternoon to measure and beats any feature table.
• Benchmark the cold path with no cache. Warm local runs favour whatever you already have cached, which is the one condition CI never has.
• Price the switching cost honestly: lockfile or config format, stricter resolution surfacing latent bugs, and every developer plus every runner having to move together.

The verdict

Public repository: stay on GitHub-hosted, which is free and unlimited there.

Private repository over your included minutes: BuildJet is a straightforward 24-41% saving depending on size, with a bigger cache allowance than GitHub-hosted and a one-line switch. Check the ARM memory ratio if you are tempted by the identical ARM pricing, and check the 64 vCPU default concurrency against your matrix width.

Private repository inside your included minutes: moving is likely a downgrade. GitHub includes 2,000 to 3,000 private-repo minutes on Free, Pro, and Team, and BuildJet offers only a one-time $5 credit, so a small project trades a zero bill for a metered one.

Frequently asked questions

Related guides

References

• BuildJet for GitHub Actions pricing (verified 2026-08-20)
• GitHub Actions billing and per-minute rates (verified 2026-08-20)
• GitHub-hosted runner specifications (verified 2026-08-20)
• GitHub Actions documentation