The canonical, dated reference

AI sandbox benchmark

As of 2026-07-26, the fastest-cold-start AI sandbox we track is Blaxel at 25ms, and the cheapest per vCPU-hour is Northflank at $0.01667. Full table below.

Last updated 2026-07-26 · figures are vendor-published; corrections welcome

SandboxIsolationCold start$/vCPU-hrGPUSession cap
Blaxel microVM 25ms $0.083 No Persistent (hibernation)
Cloudflare Sandbox SDK V8 isolate + container 50ms $0.072 No 30min execution cap
Daytona Docker container 90ms $0.05 Yes Persistent (lifecycle-managed)
E2B Firecracker microVM 150ms $0.05 No Up to 24h
Northflank Kata / gVisor microVM (selectable) 300ms $0.01667 Yes Unlimited
Fly.io Machines microVM 300ms $0.07 Yes Persistent
Vercel Sandbox Firecracker microVM 400ms $0.128 No 45min (Hobby) / 24h (Pro)
Runloop microVM 400ms $0.108 No Configurable
CodeSandbox SDK Firecracker microVM 500ms $0.05 No Configurable
Modal gVisor 800ms $0.14 Yes Configurable

Method: values are the providers' own published cold-start and pricing figures as of 2026-07-26, normalized to milliseconds and USD/vCPU-hour. Cold start varies with image size, region and warm-pool state — treat these as directional. Independent measured runs are on the roadmap; this table will carry them when live.

How to read this

Cold start and headline price are the two numbers buyers anchor on, but they rarely decide the bill alone. Isolation strength (microVM vs container), idle/paused cost, session caps, GPU availability and creation fees all move real spend. Use this table to shortlist, then model your actual workload in the cost calculator.

FAQ

Which AI sandbox has the fastest cold start?

As of 2026-07-26, Blaxel has the fastest published cold start in our benchmark at 25ms, using microVM.

Which AI sandbox is cheapest per vCPU-hour?

Northflank has the lowest published rate at $0.01667 per vCPU-hour, though total cost depends on idle time and session length.

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