E2B vs Freestyle
Both pause sandboxes with their memory, fork them and wake them on the next request. E2B gives you short-lived Firecracker microVMs in the US, EU and APAC, while Freestyle gives you full KVM VMs with nested virtualization, bigger sizes and no session cap.
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
Freestyle
Freestyle sells full Linux virtual machines for AI agents, built for long running, complex tasks.
Each Freestyle VM is a KVM virtual machine with its own kernel, booted from an Ubuntu base snapshot with systemd, Docker and coding agent CLIs preinstalled. VMs can be paused with their memory, snapshotted while running, forked and woken by the next request, and every VM starts behind a default-deny firewall. It is built for teams that give each agent or each user its own machine, driven from a TypeScript SDK, a CLI or an API.
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 | Freestyle: price rank | boat: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month Freestyle runs Docker, systemd and nested virtualization with no session cap, while E2B stops at 24 hours on Pro; boat has all of that on CPUs about twice as fast as E2B's. | 16th cheapest of 367 $4,143 a month | 241st of 367, with limits $3,311 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 hits E2B's 24-hour cap but runs on Freestyle once you leave the Free plan; boat keeps it running and a stopped boat sandbox costs nothing. | 51st of 366, with limits $5,348 a month | 263rd of 366, with limits $4,195 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 are built for this: short code runs that start fast, pause with their memory and wake on the next request. | 37th cheapest of 345 $421 a month | 40th cheapest of 345 $482 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 Both wake a paused user sandbox on its next request; boat gives each user a faster machine with a desktop and hosting built in. | 23rd cheapest of 361 $2,354 a month | 16th cheapest of 361 $1,358 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 Both fork with memory, and E2B's high start rate and 1,100 concurrent slots on Pro++ suit many short rollouts that branch from one state. | 2nd cheapest of 360 $9,384 a month | 107th of 360, with limits $6,600 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 | 53rd cheapest of 364 $1,046 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 Freestyle has nested virtualization for Android builds and E2B does not, and boat did about twice E2B's work and 2.8 times Freestyle's on the CPU benchmark. | 337th of 377, with limits $1,429 a month | 168th of 377, with limits $625 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB A dev box that runs all month needs no session cap, which Freestyle and boat have and E2B does not. | 192nd of 368, with limits $358 a month | 98th cheapest of 368 $151 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 E2B ships a Linux desktop for computer use, while on Freestyle you install the desktop, VNC and input tools yourself; boat streams its desktop at 60fps. | 32nd cheapest of 369 $1,342 a month | 234th of 369, with limits $940 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 | 257th of 367, with limits $482 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 | 278th of 346, with limits $482 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 | 183rd of 338, with limits $6,560 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 | 272nd of 360, with limits $482 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 | Freestyle | boat |
|---|---|---|---|
| Isolation | Firecracker microVM with its own kernel | Full KVM VM with its own kernel on bare metal servers | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| CPU benchmark (4 vCPU / 8 GB) | 12.61 runs/s | 9.64 runs/s | 26.69 runs/s |
| Session length | Up to 1 hour on Hobby, 24 hours on Pro; pausing resets the clock | No provider cap; a VM runs until you pause, stop or delete it | No cap on paid plans; you set the time to live |
| Biggest machine | Up to 8 vCPU / 8 GiB self-serve, more on request | Up to 32 vCPU / 64 GiB on Pro, 64 / 128 with custom limits | Up to 16 vCPU / 32 GB on the $100 plan and above |
| Nested virtualization | Not supported | Yes, full KVM support | Yes, /dev/kvm for Android emulators and VMs |
| Pause and resume | Saves memory and disk; resume takes about 1 second with processes still running | Pause saves memory and disk; the same processes resume where they left off | Disk is saved every minute and on stop; resume boots the machine again |
| Fork | Fork a running sandbox with its memory, up to 20 copies per call, with a short pause | Clone a running VM without pausing it; snapshots capture memory and disk | Fork a running sandbox with its disk |
| Wake on request | Yes; a paused sandbox can resume on the next HTTP request or SDK call | Yes; a VM paused by idle timeout resumes on the next traffic that reaches it | No; a stopped sandbox is started by API |
| Desktop and computer use | Linux desktop for computer use | Guides to install GNOME or Xvfb, VNC and Chromium yourself | Linux desktop streamed at 60fps, Chromium and computer use built in |
| Coding agents | Templates and guides for many agents, run through the command API | claude, codex, opencode and openclaw preinstalled, driven through exec or a terminal | Seven agents preinstalled, with a prompt, steer and events API |
| Keeping API keys out of the sandbox | Secrets injected into outbound HTTPS headers (private beta) | Credentials injected at the edge for HTTPS headers, Postgres and S3; the VM must trust the Freestyle CA | Credentials proxy for model providers and any HTTPS API; switch a credential to another account when credits run out |
| Inbound access | HTTPS URL per port, public by default unless you turn on a token | HTTPS on free style.dev names or your own domain, forward auth, other public protocols | HTTPS URLs for up to 50 ports, token-protected by default; raw TCP |
| Outbound rules | Allow and deny lists by IP, CIDR or domain | Default-deny firewall with allow rules by IP, VM, VPC or exact domain | Open internet, no provider-side allowlist |
| Regions and self-hosting | US, EU and APAC; open-source runtime and bring your own cloud on Enterprise | Not listed; the docs name a San Jose, US data center | EU only (Germany, Finland, France), zero data retention |
Every feature Battleships tracks (43)
| Feature | E2B | Freestyle | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | Yes | Yes |
| Nested virtualization | No | Yes | Yes |
| Root | Yes | Yes | Yes |
| Systemd | Yes | Yes | Yes |
| Desktop GUI | Yes | No | Yes |
| Browser | Yes | No | Yes |
| Computer-use API | Yes | No | Yes |
| SSH | Yes | Yes | 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 | Yes | 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 | No | No |
| GPU | No | Yes | No |
| Windows | No | No | No |
| Arm64 | No | No | No |
| Self-hosting | Yes | No | No |
| BYOC | Yes | No | No |
| Open source | Yes | No | No |
| Scoped API keys | Not published | Yes | Yes |
| Spend limits | Yes | Not published | Yes |
| Usage per sandbox (API) | No | No | Yes |
| Audit logs | Not published | Yes | No |
| SSO | No | Yes | No |
| SOC 2 | Yes | Not published | No |
| HIPAA | Yes | Not published | No |
| EU data residency | Yes | No | Yes |
| Zero data retention | Not published | Not published | Yes |
Performance
On the hpc-sandbox-benchmarks Node.js build-and-test loop at 4 vCPU / 8 GB, E2B did 12.61 runs per second and Freestyle did 9.64, so E2B finished about 1.3 times as much CPU work. boat did 26.69, about twice E2B and 2.8 times Freestyle. This measures CPU speed only, not start time, where Freestyle advertises about 65 ms.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite.
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 | Freestyle, 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 | $27 · Free | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $368 · Pro · with limits | $159 · Free | $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 | $2,139 · Pro | $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) | $581 · Pro | $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) | $1,305 · Pro · 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 more concurrency costs $500 a month per 500 slots.
Freestyle: Freestyle bills per second for the vCPU, RAM and disk allocated to a VM, busy or idle, after monthly allowances of 200 vCPU-hours, 400 GiB-hours of RAM and 60,000 GiB-hours of storage. Hobby and Pro set a $50 or $500 monthly minimum that counts as usage, and a paused VM bills only for storage.
Freestyle: Plans start at $20 a month, and the whole fee is usage credit. You pay per second while a sandbox runs, and 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 an agent that never stops, and its Pro plan includes only 20 GiB of disk. Freestyle has no session cap, but Pro allows 400 concurrent VMs, so it does not fit 1,000 short jobs at once, where E2B Pro++ does. Freestyle also has no idle timeout by default, so a VM bills until you pause it or set one. boat fits every scenario except the 1,000-job burst, where its $2,000 plan caps starts per hour and per day.
| Scenario | E2B | Freestyle | 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 | None that bite |
| 1,000 short jobs at once |
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Which one should you use?
Use E2B when
you run many short jobs that pause between requests, need very high concurrency, or must run in the US, EU or APAC or in your own cloud.
- More regions and your own cloud. E2B runs in the US, EU and APAC, its runtime is open source, and Enterprise can run in your own cloud account.
- Fast memory pause for short jobs. For short jobs that sleep between requests, a paused sandbox comes back in about a second with its processes running.
- A desktop out of the box. For computer-use agents, E2B ships a Linux desktop, while on Freestyle you install the display stack yourself.
Use Freestyle when
your VMs need nested virtualization, sessions with no cap, more than 8 vCPU in one machine, or a default-deny firewall per VM.
- Full VMs with no session cap. For long agent work, Freestyle VMs have nested virtualization and run until you stop them, while E2B stops at 24 hours.
- Bigger machines. For heavy single jobs, Freestyle Pro allows VMs up to 32 vCPU / 64 GiB, while E2B self-serve stops at 8 / 8.
- Network controls. Every VM starts behind a default-deny firewall, with private VPCs and credential injection for Postgres and S3 too.
Where boat fits
If your agents do real work for hours, like installs, builds, tests, Docker and a browser, look at boat. It gives each agent a full VM with faster CPUs than either, no session cap, a desktop built in and an API to drive the agents inside from outside.
Faster CPUs for every build
boat did 26.69 runs per second on the CPU benchmark, against 12.61 for E2B and 9.64 for Freestyle. Freestyle says it oversubscribes its hosts, and on both every install and test takes two to three times as long.
A full machine with no cutoff
On E2B a long task hits the 24-hour cap and Android emulators cannot start without nested virtualization. Freestyle has both, but on Free its monthly allowances are hard stops that pause your VM.
Agents and a desktop ready to drive
Neither has an API to prompt and steer the coding agents inside, so you parse CLI output yourself. On Freestyle you also build the desktop, VNC and click layer before a computer-use agent can start.
Use boat when your agents do real work for hours: builds, tests, Docker, emulators, a desktop and a browser, on fast CPUs, with an API to drive the agents inside from outside. Compare it one to one: boat vs E2B and boat vs Freestyle.
Questions people ask
Is E2B cheaper than Freestyle?
In most scenarios on this page, Freestyle costs less: one coding agent on workdays is $27 on Freestyle against $202 on E2B, and 50 agents in parallel are $2,139 against $2,773. For 1,000 short jobs at once, only E2B Pro++ fits, because Freestyle Pro caps at 400 concurrent VMs. boat costs less than both in every scenario.
Which is faster, E2B or Freestyle?
On the hpc-sandbox-benchmarks CPU test at 4 vCPU / 8 GB, E2B did 12.61 runs per second and Freestyle did 9.64, so E2B did about 1.3 times the work. boat did 26.69 on the same test. Freestyle advertises VM starts in about 65 ms, which this test does not measure.
Can E2B and Freestyle run Docker and Android emulators?
Both run Docker inside the sandbox. Freestyle also has full KVM support for Android emulators and VMs, while E2B's docs say nested virtualization is not supported. boat exposes /dev/kvm too.
Can a sandbox run for days on E2B or Freestyle?
Not in one E2B session: it stops after 24 hours on Pro and 1 hour on Hobby, though pausing resets the clock. Freestyle has no provider cap, but on Free its monthly allowances are hard stops. boat has no session cap on paid plans.
Do E2B and Freestyle both pause with memory?
Yes. Both save memory and disk, resume the same processes, fork running sandboxes and wake a paused one on the next request. boat saves the disk every minute and on stop, but resuming boots the machine again.
Is boat SOC 2 compliant?
SOC 2 is in progress. We're open about where we stand: live status at status.ascii.dev and our data retention policy at docs.boat.dev/data-retention.
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