E2B vs Blaxel
Both give each sandbox its own Firecracker microVM with its own kernel. E2B is built for huge numbers of short jobs and is open source, while Blaxel bills only while something is connected and drops each sandbox to standby a few seconds later.
The companies and products
E2B
E2B calls itself the AI agent cloud: an API that gives each agent session its own isolated Linux machine.
Every E2B sandbox is a Firecracker microVM that boots from a snapshot, so it starts fast and can be paused and resumed with its memory. You build custom sandboxes from templates based on a Docker image, and drive them from Python or JavaScript SDKs. It is built for teams that run many short code, data or agent jobs, and its runtime is open source.
- Isolation
- Firecracker microVM per sandbox
- Bring your own cloud
- Enterprise data plane in your AWS, GCP or Azure account
- Compliance
- SOC 2 Type II; HIPAA BAA on request
- Machine size
- 1 to 8 vCPU and 1 to 8 GiB RAM, CPU only
Blaxel
Blaxel is a San Francisco company that runs cloud infrastructure for AI agents, and since September 2026 it is part of Baseten.
You get sandboxes, batch jobs, MCP server hosting and a model gateway. Each sandbox is a Firecracker microVM with its own kernel that drops to standby when nothing is connected and resumes in under 25 ms with its memory and running processes. It is built for agent products that start many sandboxes and want them asleep most of the time.
- Headquarters
- San Francisco, founded 2024
Which use cases each one fits
For each use case, Battleships prices every sandbox provider on the same workload and sorts them from the cheapest monthly bill up. “16th cheapest of 367” means 15 of the other 366 providers run that workload, with every feature it needs, for less. “With limits” means the provider runs it but misses something, so it is listed after every full match. Open a use case for its whole ranking and what each provider misses.
| Use case and its workload | E2B: price rank | Blaxel: price rank | boat: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month Both fit, but E2B stops a session at 24 hours on Pro, Blaxel keeps files in memory unless you attach a volume, and boat gives a real disk, /dev/kvm and the fastest CPU of the three. | 16th cheapest of 367 $4,143 a month | 10th cheapest of 367 $2,373 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB An assistant that lives on its machine all month runs into E2B's 24-hour cap, while Blaxel has no session cap and sleeps between requests; boat simply keeps running. | 51st of 366, with limits $5,348 a month | 12th cheapest of 366 $2,832 a month | 5th cheapest of 366 $657 a month |
| Code interpreter bursts 100 at once · 1 vCPU / 2 GB · 200,000 sessions of 1 min a month Both suit short code runs; Blaxel sleeps right after and wakes in under 25 ms, while E2B starts fast and can wake a paused sandbox on the next request. | 37th cheapest of 345 $421 a month | 14th cheapest of 345 $144 a month | 186th of 345, with limits $2,000 a month |
| Sandboxes for your users 300 at once · 2 vCPU / 4 GB · 30,000 sessions of 23 min a month E2B sells 600 sandboxes at once on a self-serve plan, while Blaxel's public tiers stop at 200 before you talk to sales; boat fits 300 users on a self-serve plan. | 23rd cheapest of 361 $2,354 a month | 101st of 361, with limits $926 a month | Cheapest of 361 $209 a month |
| RL rollouts 1,000 at once · 2 vCPU / 4 GB · 1,000,000 sessions of 3 min a month E2B ranks 2nd here: memory forks of up to 20 copies per call and a high start rate suit many short rollouts from the same state. | 2nd cheapest of 360 $9,384 a month | 77th of 360, with limits $4,378 a month | 34th of 360, with limits $2,000 a month |
| Agent evals 250 at once · 4 vCPU / 8 GB · 15,000 sessions of 20 min a month | 78th cheapest of 364 $1,975 a month | 136th of 364, with limits $704 a month | 10th cheapest of 364 $200 a month |
| CI runners 40 at once · 8 vCPU / 16 GB · 6,000 sessions of 12 min a month E2B's 24-hour cap and slower CPU make it a compromise for CI, Blaxel fits, and boat adds /dev/kvm for Android and VM builds. | 337th of 377, with limits $1,429 a month | 57th cheapest of 377 $431 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB Neither is a plain machine to leave on: E2B caps sessions at 24 hours and Blaxel has no native SSH, while boat is a full VM you SSH into. | 192nd of 368, with limits $358 a month | 265th of 368, with limits $114 a month | 18th cheapest of 368 $26 a month |
| Computer-use agents 50 at once · 4 vCPU / 8 GB · 20,000 sessions of 15 min a month All three run a Linux desktop for computer use, and boat streams it at 60fps so you can embed it in your app. | 32nd cheapest of 369 $1,342 a month | 14th cheapest of 369 $634 a month | 6th cheapest of 369 $200 a month |
| Browser-use agents 50 at once · 2 vCPU / 4 GB · 30,000 sessions of 10 min a month | 100th of 367, with limits $746 a month | 16th cheapest of 367 $317 a month | 7th cheapest of 367 $200 a month |
| Scraping & bots (startup scale) 50 at once · 1 vCPU / 2 GB · 100,000 sessions of 3 min a month | 57th cheapest of 346 $554 a month | 16th cheapest of 346 $215 a month | 6th cheapest of 346 $90 a month |
| Mass scraping & bots (undetectable) 1,000 at once · 1 vCPU / 2 GB · 3,000,000 sessions of 2 min a month | 227th of 338, with limits $9,223 a month | 147th of 338, with limits $4,292 a month | 71st of 338, with limits $1,800 a month |
| Parallel red teaming 200 at once · 2 vCPU / 4 GB · 5,000 sessions of 30 min a month | 11th cheapest of 360 $1,043 a month | 3rd cheapest of 360 $217 a month | 2nd cheapest of 360 $200 a month |
| GPU eval jobs 10 at once · 8 vCPU / 32 GB · 500 sessions of 30 min a month | Can't run it | Can't run it | Can't run it |
| macOS agents 5 at once · 4 vCPU / 8 GB · 1,000 sessions of 20 min a month | Can't run it | Can't run it | Can't run it |
Key features
| Feature | E2B | Blaxel | boat |
|---|---|---|---|
| Isolation | Firecracker microVM with its own kernel | Firecracker microVM with its own kernel | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| CPU benchmark (4 vCPU / 8 GB) | 12.61 runs/s | 19.48 runs/s | 26.69 runs/s |
| Session length | Up to 1 hour on Hobby, 24 hours on Pro; pausing resets the clock | No session cap; Tier 0 and 1 delete sandboxes after 7 or 30 days | No cap on paid plans; you set the time to live |
| Sleep and wake | Pause with memory, resume in about 1 second; can wake on the next request (opt-in) | Standby a few seconds after the last connection, wakes in under 25 ms with memory and processes | Stop keeps the disk and costs nothing; resume boots the VM again |
| Fork | Fork a running sandbox with its memory, up to 20 copies per call | Fork with memory and running processes (private preview) | Fork a running sandbox with its disk |
| Disk | 20 GiB on Pro, 10 GiB on Hobby | Files live in memory (about half the RAM); one block volume can be attached at creation | A real disk that stays, snapshotted every minute and on stop |
| Most sandboxes at once, self-serve | 1,100 on Pro++ | 200 on Tier 2; standby sandboxes count | Up to 2,000, with limits on starts per minute, hour and day |
| Nested virtualization | Not supported | No: Firecracker guests do not get /dev/kvm | Yes, /dev/kvm for Android emulators and VMs |
| Docker inside | Yes | Yes, with a Docker-in-sandbox image | Yes, with systemd |
| Inbound access | HTTPS URL per port, public by default unless you turn on a token; no dedicated IP | Preview URL per port, public or token-protected; no raw TCP or public IP | HTTPS URLs for up to 50 ports, token-protected by default; raw TCP; dedicated IPv4 or IPv6 |
| Outbound rules | Allow and deny lists by IP, CIDR or domain | Domain allow and deny lists, method and path rules, static egress IPs | Open internet; filter inside the VM with nftables |
| Coding agents | Templates and guides for many agents, run through the command API | Claude Code image you drive from its terminal or your own harness | Claude Code, Codex and five other agents preinstalled, driven from outside with a prompt, steer and events API |
| Keeping API keys out of the sandbox | Secrets injected into outbound HTTPS headers (private beta) | Proxy fills secrets into outbound HTTPS requests (public preview) | Credentials proxy for model providers and any HTTPS API; switch a credential to another account when credits run out |
| Regions and self-hosting | US, EU and APAC; open-source runtime and bring your own cloud on Enterprise | Oregon, North Virginia, London, Frankfurt | EU only (Germany, Finland, France), with EU data residency |
Every feature Battleships tracks (43)
| Feature | E2B | Blaxel | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | Yes | Yes |
| Nested virtualization | No | No | Yes |
| Root | Yes | Yes | Yes |
| Systemd | Yes | No | Yes |
| Desktop GUI | Yes | Yes | Yes |
| Browser | Yes | Yes | Yes |
| Computer-use API | Yes | Yes | Yes |
| SSH | Yes | No | Yes |
| Persistent disk | Yes | Yes | Yes |
| Pause/resume | Yes | Yes | Yes |
| Automatic snapshots | Yes | Yes | Yes |
| Fork/clone | Yes | Yes | Yes |
| Live fork (no pause) | Yes | Yes | Yes |
| Memory fork | Yes | Yes | No |
| Custom image (Docker or snapshot) | Yes | Yes | Yes |
| ≥24 h sessions | Yes | Yes | Yes |
| Idle auto-stop | Yes | Yes | No |
| Wake on request | Yes | Yes | No |
| HTTPS preview URLs | Yes | Yes | Yes |
| Raw TCP inbound | No | No | Yes |
| Public IPv4 | No | No | No |
| Egress allowlist | Yes | Yes | No |
| Secret proxy | Yes | Yes | Yes |
| Secret proxy for any API | Yes | Yes | Yes |
| Preinstalled agents | Yes | Yes | Yes |
| Agent harness API | No | No | Yes |
| MCP server | Yes | Yes | No |
| GPU | No | No | No |
| Windows | No | No | No |
| Arm64 | No | No | No |
| Self-hosting | Yes | No | No |
| BYOC | Yes | Yes | No |
| Open source | Yes | No | No |
| Scoped API keys | Not published | Yes | Yes |
| Spend limits | Yes | No | Yes |
| Usage per sandbox (API) | No | Yes | Yes |
| Audit logs | Not published | Not published | No |
| SSO | No | Yes | No |
| SOC 2 | Yes | Yes | No |
| HIPAA | Yes | Yes | No |
| EU data residency | Yes | Yes | Yes |
| Zero data retention | Not published | Yes | Yes |
Performance
All three ran the StarSling hpc-sandbox-benchmarks Node.js build-and-test loop at 4 vCPU / 8 GB in the same run on September 29, 2026. boat did 26.69 runs per second, Blaxel 19.48 and E2B 12.61, so Blaxel did about 1.5 times the work of E2B, and boat about 1.4 times Blaxel and twice E2B. This measures CPU speed only, not start time.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Blaxel measured on: Sandbox (active time, RAM-only pricing, CPU bundled).
Pricing in five scenarios
Each bill is priced from the providers' public price lists by the open Battleships engine, with the cheapest plan that runs the scenario.
| Scenario | E2B, a month | Blaxel, a month | boat, a month |
|---|---|---|---|
| One coding agent, workdays 4 vCPU / 8 GB, 50 GB disk, 8 hours a day, 22 days a month, files kept between days | $202 · Pro | $33 · Pay-as-you-go Tier 1 | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $368 · Pro · with limits | $120 · Pay-as-you-go Tier 1 | $26 · $20/mo |
| 50 agents in parallel 50 machines of 4 vCPU / 8 GB at once, 8-hour sessions, 1,100 sessions a month, Docker inside | $2,773 · Pro | $1,489 · Pay-as-you-go Tier 1 | $317 · $20/mo × 3 seats |
| Sandboxes for your users 2 vCPU / 4 GB, 30,000 sessions of 10 minutes a month, up to 300 at once | $1,395 · Pro+ (600 concurrent) | $396 · Pay-as-you-go Tier 2 · with limits | $200 · $100/mo × 2 seats |
| 1,000 short jobs at once 2 vCPU / 4 GB, 1,000 at once, 3 minutes each, 200,000 jobs a month | $2,797 · Pro++ (1,100 concurrent) | $876 · Pay-as-you-go Tier 2 · with limits | $2,000 · $2000/mo · with limits |
E2B: E2B bills per second for the vCPU and RAM you set, idle time included, until you pause or kill the sandbox. Pro costs $150 a month for higher limits with no usage credit, and each 500 extra concurrent slots cost $500 a month.
Blaxel: Blaxel charges for allocated RAM per second while a sandbox has an open connection, with CPU included. In standby you pay only snapshot storage, and tier top-ups go to your wallet as usage credit.
Blaxel: Plans start at $20 a month, and the whole fee is usage credit billed per second while a sandbox runs. A stopped sandbox costs nothing and keeps its disk.
Limits in those scenarios
E2B caps a session at 24 hours on Pro, so it does not fit the always-on agent, and its Pro disk is 20 GiB. Blaxel has no session cap, but its self-serve tiers stop at 200 sandboxes at once, standby ones included, so it does not fit 300 users or 1,000 short jobs at once without a sales tier. E2B Pro++ fits 1,000 jobs at once and only queues bursts above 300 starts a minute, while boat caps starts per hour and per day there.
| Scenario | E2B | Blaxel | boat |
|---|---|---|---|
| One coding agent, workdays |
| None that bite | None that bite |
| One agent that never stops |
| None that bite | None that bite |
| 50 agents in parallel |
| None that bite | None that bite |
| Sandboxes for your users |
|
| None that bite |
| 1,000 short jobs at once |
|
|
|
Which one should you use?
Use E2B when
you run very large bursts of short jobs, need memory forks for rollouts, want an open-source runtime, or must run in APAC.
- Built for very high scale. E2B sells up to 1,100 sandboxes at once on a self-serve plan, so big bursts of short jobs need no sales call.
- Memory forks for branching work. For RL rollouts and evals, E2B can fork a running sandbox with its memory into up to 20 copies in one call.
- Open source and more regions. Its runtime is Apache-2.0 and can run on your own host, and it runs in APAC as well as the US and EU.
Use Blaxel when
your sandboxes sit idle most of the time and must wake in milliseconds, or run for days with no session cap, in the US or EU.
- You pay only while connected. Blaxel bills RAM only while a sandbox is active and drops it to standby seconds after the last connection, so idle time costs little.
- No session cap. A Blaxel sandbox can stay up for as long as you like, while E2B stops a session at 24 hours on Pro.
- Finer network rules and a faster CPU. Blaxel can limit traffic down to methods and paths with static egress IPs, and it ran the CPU benchmark about 1.5 times faster.
Where boat fits
E2B and Blaxel are both microVMs tuned to sleep and wake quickly. If your agents do long, heavy work like installs, builds, tests, Docker and emulators, boat gives each one a full Linux machine with a real disk and a faster CPU, and drives the agents inside from outside.
A whole Linux machine
Neither E2B nor Blaxel exposes /dev/kvm, so an Android emulator or a VM does not start at all, and Blaxel has no native SSH. boat has /dev/kvm, systemd, real SSH and raw TCP.
The fastest CPU of the three
On the same benchmark boat did 26.69 runs per second, Blaxel 19.48 and E2B 12.61. Every build and test waits about twice as long on E2B and 1.4 times as long on Blaxel.
A disk that stays and agents built in
E2B ends a session at 24 hours on Pro, and Blaxel keeps files in memory unless you attach a volume. boat saves a real disk every minute, has no session cap, and ships seven agents with a driving API.
Use boat when your agents do real work for hours: installs, builds, tests, Docker and emulators on a full Linux machine with a real disk, the fastest CPU here and agents built in. Compare it one to one: boat vs E2B and boat vs Blaxel.
Questions people ask
Is E2B cheaper than Blaxel?
No, Blaxel costs less in every scenario we priced: one coding agent on workdays is $33 a month on Blaxel against $202 on E2B, and 50 agents in parallel $1,489 against $2,773. Blaxel's public tiers do not fit 300 users or 1,000 jobs at once, which E2B covers on Pro+ and Pro++. boat is $20 and $317 for those first two.
Which is faster, E2B or Blaxel?
On the hpc-sandbox-benchmarks CPU test at 4 vCPU / 8 GB, Blaxel did 19.48 runs per second and E2B 12.61, about 1.5 times the work. boat did 26.69 in the same run.
Can E2B or Blaxel run Docker and Android emulators?
Both run Docker inside the sandbox; Blaxel uses a Docker-in-sandbox image. Neither exposes /dev/kvm, so Android emulators and VMs do not start, while boat has /dev/kvm in every sandbox.
Can an E2B or Blaxel sandbox run for days?
On E2B, not in one session: it stops after 24 hours on Pro and 1 hour on Hobby, though pausing resets the clock. Blaxel has no session cap, but Tier 0 and 1 delete sandboxes after 7 or 30 days. boat has no session cap on paid plans.
Do E2B and Blaxel keep memory when a sandbox sleeps?
Yes, both. E2B pauses with memory and resumes in about a second, and Blaxel goes to standby on its own and wakes in under 25 ms. boat keeps the disk and reboots on resume.
Where do E2B and Blaxel run?
E2B runs in the US by default, with EU and APAC on Pro and above. Blaxel runs in Oregon, North Virginia, London and Frankfurt. boat runs only in the EU, in Germany, Finland and France.
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