E2B gives an application short-lived, isolated cloud sandboxes where an AI agent can actually execute code, not just suggest it, with a free Hobby tier ($100 in credits, no card) before Pro starts at $150/month plus usage. Pick it when you're building an agent that needs to run untrusted or generated code somewhere other than your own machine.
Other good fits
Testing untrusted or AI-generated code in an isolated environment instead of your own machine or production server.
+ Pros
Read pros
E2B provides isolated, short-lived cloud sandboxes an application can spin up on demand, so an AI agent can actually run code (install packages, execute scripts, read and write files) instead of only generating text that describes what code would do. It's aimed at developers building agents or coding tools that need real execution, safely separated from your own infrastructure.
Pick it when…
You're building an agent that needs to execute generated or untrusted code, not just produce it as text.
You want isolation between what the agent runs and your own production systems.
You want to try the concept without commitment; the Hobby tier's $100 in credits needs no credit card to start.
− Cons
Read cons
Sandbox isolation reduces risk but doesn't make agent-run code automatically safe to trust with real credentials or production data; treat a sandbox as isolated compute, not a security guarantee for everything you might connect it to. Session duration caps (1 hour on Hobby, 24 hours even on Pro) mean this isn't built for long-running background jobs.
Pick something else when…
You don't need code execution, just generation. Call a model API directly instead of adding a sandbox layer.
You need sessions longer than 24 hours. E2B's sandboxes are built for short-lived execution, not long-running services.
You want the sandbox bundled into a broader agent framework rather than integrating it yourself. The Claude Agent SDK includes its own tool-execution model.
Avoid if
You need sessions longer than a day; the maximum session duration is 24 hours even on the Pro plan.
Workflow
Spin up a sandbox from your application code → let the agent write and execute code inside it → capture output, files or errors back into your application → let the sandbox expire (sessions are capped, 1 hour on Hobby, 24 hours on Pro) or tear it down explicitly → size CPU and RAM to the task rather than defaulting to the largest option.
Beyond the base fee, usage is billed per second: about $0.000014 per vCPU-second and $0.0000045 per GiB-second, with a default sandbox at 2 vCPUs and 4 GiB RAM (customisable from 1–8 of each). Storage itself carries no extra fee. The running cost scales with how long sandboxes stay open and how many run concurrently, so an agent that leaves sandboxes idle costs more than one that tears them down promptly.
Restrictions
Maximum session duration is capped at 1 hour on Hobby and 24 hours on Pro; nothing here is meant for long-running processes. Enterprise pricing has a $3,000/month minimum, a meaningful jump from Pro's $150 base.
First project
Documentation-based suggestion — not run here.
Build a small pipeline: an agent that receives a made-up dataset description, writes a short data-analysis script, and runs it in an E2B sandbox to produce a chart or summary. Check that the sandbox's output matches what you'd expect from running the same script yourself.
Done when the agent-written script runs successfully in the sandbox and produces output you've independently verified is correct for the (fictional) input data.
Links & evidence
Documentation-based · not hands-on · Sep 23, 2026
Rests on E2B's pricing page, read on 2026-09-23. No sandbox was created or run for this review.
E2B homepage · Sep 23, 2026 — Cloud sandboxes for AI agent code execution.
Claude Agent SDK overview · Sep 23, 2026 — Comparison alternative with a built-in tool-execution model.
Further review notes & alternatives
Alternatives and trade-offs
Claude Agent SDK wins when you want code execution bundled into a broader agent framework rather than integrating a separate sandbox service.
Running your own containerised sandbox wins when you need longer sessions or full control over the execution environment, at the cost of building and securing it yourself.
A plain model API call wins when the task is generation only, with no execution required.
Run code and agent tools inside isolated cloud sandboxes.
Use Node.js or Python SDKs to automate sandboxed execution.
Self-host the infrastructure when you need deployment control.
free-tier · cloud · self-host
agent sandbox
code execution
isolation
sdk
virtual computer
write-code
open-source
View sourced imageOfficial E2B Desktop Sandbox screenshot from the E2B Desktop repository. This is the sandboxed Linux desktop available through E2B's computer-use SDK, not the E2B account-management console. No sandbox was started for this acquisition.
E2B official Desktop Sandbox repository
Owner-requested editorial use of an official public interface image, 18 September 2026. Copyright remains with the original publisher; attribution preserved. No open licence, current plan entitlement or independent execution is asserted. Source asset: https://raw.githubusercontent.com/e2b-dev/desktop/main/readme-assets/screenshot.png. Complete image/frame converted to PNG without overlays or content changes.