Cloudflare Sandbox vs GitHub Codespaces

Cloudflare Sandbox is a sandbox you drive from code: a container in its own microVM, started from your Worker, that sleeps when idle and comes back with a fresh disk. GitHub Codespaces is a dev environment for people: a dev container opened from a repository in VS Code or the browser, that keeps its files but stops after 12 hours at most.

The companies and products

Cloudflare Sandbox

Cloudflare Sandbox SDK runs untrusted or AI-generated code in Linux containers on Cloudflare's network, driven from a Cloudflare Worker.

Each sandbox is a Cloudflare Container backed by a Durable Object, and each container runs in its own Firecracker microVM with its own kernel and network. You build a linux/amd64 image, pick an instance type of up to 4 vCPU and 12 GiB, and reach the sandbox through your own Worker. It suits teams already on Workers who want short-lived sandboxes that sleep when idle; for code that only calls known methods, Cloudflare also offers Dynamic Workers, which run JavaScript in V8 isolates.

Isolation: Firecracker microVM per container, own kernel and network
Largest instance: 4 vCPU, 12 GiB memory, 20 GB disk (defaults, can be raised)
Disk: Ephemeral by default: a container that sleeps starts again from a fresh disk
Plan needed: Workers Paid, $5 a month account minimum; not on the Free plan
Account limits: 1,500 vCPU, 6 TiB memory and 30 TB disk running at once
Placement: Instances spread across several regions of Cloudflare's network, nearest free one picked
Compliance: Cloudflare holds a SOC 2 Type II report

GitHub Codespaces

GitHub Codespaces is GitHub's cloud development environment: a ready-to-code Linux machine for a repository, opened in the browser, VS Code or the GitHub CLI.

Codespaces is a different kind of product from boat: a dev environment for people working on a GitHub repository, not a sandbox API for agents. Each codespace is a Docker container built from the repo's dev container config, running on its own newly built VM on Azure, with 2 to 32 cores. It is built for developers and teams who want every contributor to start from the same setup, with prebuilds, port forwarding and GitHub billing.

Isolation: A Docker container on its own newly built VM, with its own virtual network
Operating system: Linux only; Windows and macOS are not supported for the remote container
Machine sizes: 2, 4, 8, 16 or 32 cores, with 4 GB of memory per core
Lifetime: Stops after 30 idle minutes by default (5 to 240), and after 12 hours at most even while in use
Regions: US East, US West, Europe West and Southeast Asia
Free usage: Personal Free accounts get 120 core-hours and 15 GB-month a month, Pro 180 and 20; organizations get no free quota
Compliance: GitHub Enterprise Cloud lists SOC 1, SOC 2 and SOC 3 reports and ISO 27001

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. “13th cheapest of 345” means 12 of the other 344 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	Cloudflare Sandbox: price rank	GitHub Codespaces: price rank	boat: price rank
Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month Long build-and-test loops hit a wall on both: Cloudflare resets the disk when a container sleeps, and a codespace stops after 12 hours; boat keeps the disk and runs until you stop it.	162nd of 367, with limits $1,543 a month	274th of 367, with limits $4,618 a month	3rd cheapest of 367 $634 a month
Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB An always-on assistant needs its files and logins to stay put; Cloudflare wipes the disk on sleep, Codespaces stops every 12 hours, and boat keeps running with its disk.	207th of 366, with limits $2,188 a month	309th of 366, with limits $6,970 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 For short code-interpreter calls Cloudflare Sandbox ranks 13th, since CPU is billed only while busy and a container wakes on the next request, while each codespace builds a dev container on a new VM.	13th cheapest of 345 $144 a month	288th of 345, with limits $619 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 Cloudflare fits sandboxes for your own users and adds egress rules in Worker code; Codespaces are made for GitHub users on a repository and GitHub does not publish how many can run at once.	9th cheapest of 361 $731 a month	281st of 361, with limits $1,964 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	144th of 360, with limits $9,428 a month	282nd of 360, with limits $9,489 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 Cloudflare fits agent evals as many short, separate sandboxes; on Codespaces every copy is created again from the repository, and boat can fork one prepared machine while it runs.	45th cheapest of 364 $818 a month	295th of 364, with limits $1,519 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 Neither is a natural CI box: Cloudflare caps disk at 20 GB by default and runs Docker with iptables off, and Codespaces has no fork or snapshot API.	301st of 377, with limits $704 a month	314th of 377, with limits $909 a month	4th cheapest of 377 $86 a month
24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB Codespaces is the more polished dev box for a person, with VS Code and files kept between days, but it stops after 12 hours at most; Cloudflare starts from a fresh disk after sleep.	70th cheapest of 368 $93 a month	130th of 368, with limits $270 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 Neither ships a graphical desktop: Cloudflare removed its built-in one and Codespaces gives you an editor and a terminal, while boat streams a 60fps desktop with Chromium.	166th of 369, with limits $460 a month	267th of 369, with limits $1,367 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	210th of 367, with limits $233 a month	275th of 367, with limits $678 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	250th of 346, with limits $286 a month	310th of 346, with limits $922 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	169th of 338, with limits $5,741 a month	280th of 338, with limits $18,637 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	239th of 360, with limits $325 a month	267th of 360, with limits $445 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	Cloudflare Sandbox	GitHub Codespaces	boat
What it is	Sandbox SDK: Linux containers you start and drive from a Cloudflare Worker	Cloud dev environment opened from a GitHub repository in VS Code, the browser or the CLI	Sandbox API: full VMs you create, fork and drive from code
Isolation	Firecracker microVM per container, own kernel and network	A Docker container on its own newly built VM, with its own virtual network	Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts
Largest machine	4 vCPU / 12 GiB / 20 GB disk by default (can be raised)	2, 4, 8, 16 or 32 cores, with 4 GB of memory per core	Up to 16 vCPU / 32 GB, depending on plan
How long it runs	No fixed maximum runtime, but none guaranteed; host restarts can stop it and wipe its state	Stops after 30 idle minutes by default (up to 240) and after 12 hours at most, even while in use	Runs until you stop it; no session cap on paid plans
Files after a stop	Fresh disk after sleep; snapshots (public beta, 30 days) or R2 backups when your code saves them	Saved files are kept and storage is billed; stopped codespaces are deleted after 30 days by default	Disk snapshotted every minute and on stop; a stopped sandbox keeps its disk and costs nothing
Fork a running sandbox	No fork; restore a saved snapshot or backup into a new sandbox	No copy or snapshot endpoint; new codespaces start from a repo, branch, pull request or prebuild	Yes, without stopping it
Docker and nested virtualization	docker:dind with iptables and IP forwarding turned off; nested virtualization not documented	Docker and sudo inside the dev container; /dev/kvm not documented	Full Docker, root, systemd and /dev/kvm on every machine
Desktop and computer use	Built-in desktop removed in SDK 0.10.2; bring your own	VS Code, JupyterLab and a terminal; no graphical desktop	60fps desktop and Chromium, computer-use API, embeddable stream
Reaching the sandbox	HTTP and WebSocket previews routed through your Worker; no raw TCP or public IP	A URL per forwarded port, plus SSH and CLI tunnels; no public IP	HTTPS URLs for up to 50 ports, token-protected; raw TCP; own IPv6 or IPv4
Egress control	allowedHosts deny-by-default list plus outbound handlers you write in Worker code	Open internet; GitHub says there is no way to restrict it	Open internet; no provider-side allowlist
Keeping keys out of the sandbox	Your outbound handler adds the token for any HTTP or HTTPS host; you write the code	Secrets are copied into the codespace as environment variables	Managed proxy for model providers and any HTTPS API you register; switch a credential to another account
Coding agents	Run Claude Code, Codex, OpenCode or Pi in your image; OpenCode has an SDK helper	GitHub Copilot as a VS Code extension; other agents you install and run yourself	Claude Code, Codex, OpenCode and more built in, with a prompt, steer and events API
Sleep when idle	Stops after inactivity and wakes on the next request	Stops after the idle timeout; you restart it from the editor, CLI or API	TTL based (1 h default, changeable); no idle timer
Regions	Several regions across Cloudflare's network, nearest free instance picked	US East, US West, Europe West and Southeast Asia	EU only: Germany, Finland, France

Every feature Battleships tracks (43)

Feature	Cloudflare Sandbox	GitHub Codespaces	boat
Full VM (own kernel)	Yes	Yes	Yes
Docker inside	Yes	Yes	Yes
Nested virtualization	No	No	Yes
Root	Yes	Yes	Yes
Systemd	Not published	Not published	Yes
Desktop GUI	No	No	Yes
Browser	No	No	Yes
Computer-use API	No	No	Yes
SSH	Yes	Yes	Yes
Persistent disk	No	Yes	Yes
Pause/resume	No	Yes	Yes
Automatic snapshots	No	No	Yes
Fork/clone	No	No	Yes
Live fork (no pause)	No	No	Yes
Memory fork	No	No	No
Custom image (Docker or snapshot)	Yes	Yes	Yes
≥24 h sessions	Yes	No	Yes
Idle auto-stop	Yes	Yes	No
Wake on request	Yes	No	No
HTTPS preview URLs	Yes	Yes	Yes
Raw TCP inbound	No	No	Yes
Public IPv4	No	No	No
Egress allowlist	Yes	No	No
Secret proxy	Yes	No	Yes
Secret proxy for any API	Yes	No	Yes
Preinstalled agents	Yes	No	Yes
Agent harness API	Yes	No	Yes
MCP server	No	No	No
GPU	No	No	No
Windows	No	No	No
Arm64	No	No	No
Self-hosting	No	No	No
BYOC	No	No	No
Open source	Yes	No	No
Scoped API keys	Not published	Not published	Yes
Spend limits	No	Yes	Yes
Usage per sandbox (API)	Not published	No	Yes
Audit logs	Yes	Yes	No
SSO	Yes	Yes	No
SOC 2	Yes	Yes	No
HIPAA	Yes	No	No
EU data residency	Yes	Yes	Yes
Zero data retention	Not published	Not published	Yes

Performance

Cloudflare SandboxNot measured

GitHub CodespacesNot measured

boat26.69 runs/s

Neither Cloudflare Sandbox nor GitHub Codespaces has a result on the hpc-sandbox-benchmarks Node.js build-and-test loop, so there is no comparable CPU number between them. boat did 26.69 runs per second at 4 vCPU / 8 GB in StarSling's run of 2026-09-29, on dedicated AMD Ryzen 9 9950X hosts.

Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Cloudflare Sandbox and GitHub Codespaces have no published run in this suite yet, so there is no like-for-like number to compare.

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	Cloudflare Sandbox, a month	GitHub Codespaces, 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	$39 · Workers Paid · with limits	$51 · Personal account: GitHub Free	$20 · $20/mo
One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month	$148 · Workers Paid · with limits	$270 · Personal account: GitHub Free · with limits	$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	$1,660 · Workers Paid · with limits	$3,019 · Personal account: GitHub Free	$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	$476 · Workers Paid	$850 · Personal account: GitHub Free · 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	$1,889 · Workers Paid · with limits	$1,889 · Personal account: GitHub Free · with limits	$2,000 · $2000/mo · with limits

Cloudflare Sandbox: You need Workers Paid ($5 a month minimum). CPU is billed only while in use; memory and disk are billed on the instance size, in 10 ms steps, until the container sleeps, and 4 vCPU always comes with 12 GiB.

GitHub Codespaces: Codespaces bills $0.09 per core-hour while a codespace is active, used or not, plus $0.07 per GB-month of storage while it exists, stopped too. Personal accounts get a free monthly quota; organizations do not.

GitHub Codespaces: You pick a monthly plan from $20, and all of it becomes usage credit spent per second on running sandboxes. A stopped sandbox costs nothing and keeps its disk.

Limits in those scenarios

Cloudflare's disk resets after sleep, so the scenarios that keep 50 GB of files between days do not fit without your own snapshot or backup code, and its 1,500 vCPU account cap is short of the 2,000 vCPU the 1,000-job burst needs. Codespaces keeps files, but every codespace stops after 12 hours, so it misses the always-on scenario, and GitHub does not publish how many can run at once, so 300 user sandboxes and 1,000 short jobs are not confirmed. boat fits all but the burst, where the $2,000 plan allows 600 starts an hour and bursts above 90 starts a minute wait in a queue.

Scenario	Cloudflare Sandbox	GitHub Codespaces	boat
One coding agent, workdays	missing persistent disk	None that bite	None that bite
One agent that never stops	missing persistent disk	Personal account: GitHub Free: sessions capped at 12 h	None that bite
50 agents in parallel	missing persistent disk	how many machines can run at once: limit not published, probably fine at 50 (the typical published limit is 50)	None that bite
Sandboxes for your users	None that bite	not confirmed: how many machines can run at once (you need 300; the typical published limit is 50)	None that bite
1,000 short jobs at once	Workers Paid: max 1,500 vCPU running at once (needs 2,000)	not confirmed: how many machines can run at once (you need 1,000; the typical published limit is 50)	max 2,400 starts/day (needs ~6,667) max 600 starts/hour (needs ~1,000) bursts above 90 starts/min are queued (a burst of 333 takes ~4 min to start)

Which one should you use?

Use Cloudflare Sandbox when

your app already runs on Workers and you want many short sandboxes that sleep when idle, wake on the next request and follow egress rules you program.

Egress rules you can program. Useful when sandboxes run untrusted code: block every host except the ones you list, and run your own code on each outbound request.
Sleeps when idle, wakes on request. Useful for many short, spiky sessions: a sandbox sleeps when idle, wakes on the next request, and bills CPU only while busy.
Part of the Workers platform. If your app already runs on Workers, sandboxes sit next to Durable Objects and R2, in several regions.

Use GitHub Codespaces when

your developers want a ready VS Code environment for a GitHub repository, opened from a branch or pull request, with files kept between days.

Built into GitHub. Useful if your team lives on GitHub: open a codespace from any repo, branch or pull request, with the dev container already set up.
Bigger machines for people. Useful for heavy local-style work: machines go up to 32 cores with 4 GB of memory per core, and files stay between days.
Free hours for personal accounts. Useful for occasional personal work: a GitHub Free account includes 120 core-hours and 15 GB-month of storage each month.

Where boat fits

If what you are really running is coding agents that work for hours, neither product was built for that: Cloudflare forgets the disk when a sandbox sleeps, and Codespaces is a dev box for people that stops at 12 hours. boat gives each agent a full VM that keeps running and keeps its files, with Docker, /dev/kvm, a desktop and the agents already installed.

Work that survives the night

Cloudflare starts a slept sandbox from a fresh disk unless your code saves a snapshot or R2 backup, and a codespace stops at 12 hours, ending its processes. boat runs until you stop it, saves the disk every minute and forks while running.

A full machine, not a container

On Cloudflare, Docker runs with iptables off, disk is 20 GB by default and there is no desktop. Codespaces documents no /dev/kvm, no graphical desktop and no public IP. boat has systemd, /dev/kvm, a 60fps desktop and raw TCP.

Agents driven from outside, keys kept out

On Cloudflare you bake each agent into your image and write the outbound handler that adds tokens. On Codespaces you script agents over SSH, and secrets sit in environment variables. boat ships agents with a prompt, steer and events API and a credentials proxy.

Use boat when your code starts agents that work for hours or days: full VMs with Docker, /dev/kvm and a desktop, coding agents built in with keys kept outside, and machines that keep their work and fork while running. Compare it one to one: boat vs Cloudflare Sandbox and boat vs GitHub Codespaces.

Questions people ask

Is Cloudflare Sandbox cheaper than GitHub Codespaces?

In our scenarios Cloudflare's estimate is lower: one agent all month is $148 against $270, 50 agents $1,660 against $3,019, and 300 user sandboxes $476 against $850. But Cloudflare only fits the user-sandbox scenario, since the others need files kept between sessions. boat comes to $26, $317 and $200 for the same three.

Which is faster, Cloudflare Sandbox or GitHub Codespaces?

There is no comparable measurement: neither has a result on the benchmark we use. boat did 26.69 Node.js build-and-test runs per second at 4 vCPU / 8 GB.

Can I run Docker in Cloudflare Sandbox or GitHub Codespaces?

Yes, with limits. Cloudflare supports docker:dind with iptables and IP forwarding turned off, and Codespaces runs Docker inside the dev container with sudo, but neither documents /dev/kvm. boat runs full Docker with systemd and /dev/kvm.

Can an AI agent run 24/7 on either one?

Not easily. Codespaces stops every codespace after 12 hours, even while in use. Cloudflare has no fixed maximum runtime but guarantees none, and a stopped or slept container comes back with a fresh disk. A boat sandbox runs until you stop it, with no session cap on paid plans.

Which one keeps my files?

Codespaces keeps saved files when a codespace stops, and deletes stopped codespaces after 30 days by default. Cloudflare starts from a fresh disk after sleep unless your code saved a snapshot (public beta, 30 days) or an R2 backup. boat keeps the disk on its own and snapshots it every minute.

Where do they run?

Cloudflare places containers in several regions of its network and picks the nearest free instance. Codespaces runs in US East, US West, Europe West and Southeast Asia. boat runs only in the EU, in Germany, Finland and France.

Try boat

Install the CLI, then run boat new.

7-day free trial