10 tracked

AI Agent & Code-Execution Sandboxes

Ephemeral, secure runtimes — microVMs and containers — that spin up in milliseconds so agents and apps can execute generated code safely. Compared on cold start, isolation, pricing, GPU, persistence and SDK support.

Data last verified 2026-07-26

Compare at a glance

SandboxIsolationCold start$/vCPU-hrGPUSessionMCP
Blaxel microVM25ms$0.083NoPersistent (hibernation)Yes
Cloudflare Sandbox SDK V8 isolate + container50ms$0.072No30min execution capYes
Daytona Docker container90ms$0.05YesPersistent (lifecycle-managed)Yes
E2B Firecracker microVM150ms$0.05NoUp to 24h
Northflank Kata / gVisor microVM (selectable)300ms$0.01667YesUnlimited
Fly.io Machines microVM300ms$0.07YesPersistentYes
Vercel Sandbox Firecracker microVM400ms$0.128No45min (Hobby) / 24h (Pro)
Runloop microVM400ms$0.108NoConfigurableYes
CodeSandbox SDK Firecracker microVM500ms$0.05NoConfigurable
Modal gVisor800ms$0.14YesConfigurable

Figures are vendor-published approximations as of the verified date. Tap a name for sources.

All ai sandboxes

AI code-execution sandbox

Blaxel

Blaxel is an idle-cost-optimized sandbox that resumes from hibernation in ~25ms with memory and processes intact, and charges $0 for compute on standby.

25ms cold start Compare →
AI code-execution sandbox

Cloudflare Sandbox SDK

Cloudflare Sandbox SDK runs code on Cloudflare Containers + Durable Objects, blending V8 isolates (sub-50ms) with containers, bundled into the Workers Paid plan.

50ms cold start Compare →
AI code-execution sandbox

Daytona

Daytona is an open-source, container-isolated sandbox for AI agents with sub-90ms creation, persistent stateful workspaces, mid-execution snapshots and optional H100 GPUs.

90ms cold start Compare →
AI code-execution sandbox

E2B

E2B is a Firecracker-microVM sandbox that gives AI agents a secure, ~150ms-cold-start environment to run generated code, with pause/resume and filesystem snapshots.

150ms cold start Compare →
AI code-execution sandbox

Northflank

Northflank runs sandboxes with selectable Kata/gVisor microVM isolation, unlimited session duration, any OCI image and BYOC deployment — at the lowest published vCPU rate in the category.

300ms cold start Compare →
AI code-execution sandbox

Fly.io Machines

Fly.io Machines are fast-booting microVMs with a persistent ext4 filesystem, ~300ms checkpoints, zero idle cost and a native MCP endpoint.

300ms cold start Compare →
AI code-execution sandbox

Vercel Sandbox

Vercel Sandbox is a Firecracker-based, JavaScript/TypeScript-native sandbox that is persistent by default, billed on active CPU plus a per-creation fee.

400ms cold start Compare →
AI code-execution sandbox

Runloop

Runloop provides enterprise "devbox" infrastructure for coding agents — SOC 2, 10K+ parallel instances, git-style disk snapshots with branching, and built-in SWE-bench evaluation.

400ms cold start Compare →
AI code-execution sandbox

CodeSandbox SDK

CodeSandbox SDK (now Together Code Sandbox) runs Firecracker microVMs with a git-versioned filesystem, ~500ms resume and sub-second forking, tuned for web-dev agents.

500ms cold start Compare →
AI code-execution sandbox

Modal

Modal is a Python-first serverless compute platform whose Sandboxes offer gVisor isolation, sub-second cold start and — uniquely — GPUs (T4 through B200) inside the sandbox.

800ms cold start Compare →

FAQ

What is an AI agent sandbox?

An AI agent sandbox is an isolated compute environment — usually a microVM or container — where an AI agent can execute generated code securely, without risking the host. Key attributes are cold-start time, isolation strength, pricing, persistence and GPU support.

Which AI sandbox has the fastest cold start?

Among tracked providers, V8-isolate and hibernation-based options are fastest (Cloudflare isolates ~50ms, Blaxel resume ~25ms), while Firecracker microVMs like E2B land around 150ms. Full container/microVM cold starts range up to a few seconds.

Which AI sandboxes support GPUs?

Modal, Daytona, Northflank and Fly.io offer GPU access inside or alongside the sandbox; Modal is the standout for GPU-in-sandbox workloads.

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