Compare / Sandboxes
E2B vs Cloudflare Sandbox
E2B is cheaper: about $0.17 an hour for 2 vCPU and 4 GiB, against $0.18 on Cloudflare Sandbox with the CPU busy all hour (Cloudflare Sandbox bills CPU only while it is busy, so idle time costs less there). E2B was faster on a real coding-agent build: 75.9 s against 189.9 s.
At a glance
| E2B | Cloudflare Sandbox | |
|---|---|---|
| Isolation | Firecracker microVM | Firecracker microVM per instance, with your image running as a container inside it |
| Price | $0.000014 per vCPU-second and $0.0000045 per GiB-second. | $0.000020 per vCPU-second, billed only while the CPU is active, and $0.0000025 per GiB-second of provisioned memory (calc: $0.072 per vCPU-hour, $0.009 per GiB-hour). You also pay for the Worker requests and Durable Object behind each sandbox. |
| 2 vCPU, 4 GiB for an hour | $0.17 | $0.18 if the CPU is busy all hour |
| Free tier | One-time $100 credit on the free Hobby plan. Pro is $150 a month plus usage. | Needs the Workers Paid plan ($5 a month), which includes 375 vCPU-minutes, 25 GiB-hours of memory and 200 GB-hours of disk a month. |
| Longest session | 1 hour on Hobby, 24 hours on Pro. Pausing resets the clock. | No hard maximum, but runtime isn't guaranteed. By default a sandbox sleeps after 10 minutes idle; keepAlive stops it sleeping. |
| Largest sandbox | 8 vCPU and 8 GiB (default 2 vCPU, 4 GiB) | 4 vCPU, 12 GiB and 20 GB disk (standard-4) |
| Pause and persistence | Pause keeps memory and files, about 4 s per GiB to pause and 1 s to resume. Paused sandboxes are kept indefinitely. | Disk is ephemeral by default: files and processes are lost when it sleeps. Snapshots save the filesystem only, kept 30 days. |
| Start time (published) | Not published in milliseconds; boots from a snapshot. | Often 1 to 3 s, depending on image size. |
| GPUs | No | Not stated |
| Self-hosting | Yes. The infrastructure is open source under Apache-2.0, with Terraform for Google Cloud, AWS and Azure, and a single-host option. | No. The SDK is open source (Apache-2.0); the runtime is Cloudflare-hosted. |
| SDKs | Python, JavaScript/TypeScript | TypeScript/JavaScript, run from a Worker |
| Real build benchmark | 7 of 7 phases, 75.9 s | 7 of 7 phases, 189.9 s |
On a real coding-agent build
The open-source ComputeSDK sandbox-dax benchmark runs OpenCode's provider benchmark in each sandbox: install packages and Bun, clone OpenCode, bun install, then bun typecheck. Results from the run of 30 October 2026:
- E2B completed all seven phases in 75.9 s on a sandbox reporting 8 CPUs and about 16 GiB: clone 3.0 s, install 17.2 s, typecheck 40.8 s.
- Cloudflare Sandbox completed all seven phases in 189.9 s on a sandbox reporting 8 CPUs and about 16 GiB: clone 5.9 s, install 75.0 s, typecheck 72.6 s.
Each provider is one run, and sandboxes report different CPU counts, so treat small gaps as noise. For what this build needs from a sandbox, and what isolation costs, see our benchmark write-up.
Which should you choose?
Choose E2B if
- price per hour matters most
- your agents run heavy builds and speed matters
- you need pause and resume that keeps memory, not just files
- you may need to run it in your own cloud or data center
If neither fits because your code and API keys must stay on your own hardware, Hotcell runs sandboxes on machines you control, and Directionally Local sets it up with the Autopilot coding agent harness in one command. More options: E2B alternatives.
More comparisons
Sources
- E2B: E2B pricing
- E2B: E2B persistence docs
- E2B: e2b-dev/infra
- Cloudflare Sandbox: Cloudflare Containers pricing
- Cloudflare Sandbox: Cloudflare Sandbox docs
- Cloudflare Sandbox: Sandbox lifetime
- Benchmark: ComputeSDK sandbox-dax results
Prices change often. We check them by hand and the benchmark refreshes on every build; if something here is out of date, tell us.
FAQs
Is E2B cheaper than Cloudflare Sandbox?
E2B is cheaper. A sandbox with 2 vCPU and 4 GiB running for an hour costs about $0.17 there, against $0.18 on Cloudflare Sandbox. Cloudflare Sandbox bills CPU only while it is busy, so idle sandboxes cost less there than this suggests.
Which is faster, E2B or Cloudflare Sandbox?
E2B completed all seven phases in 75.9 s on a sandbox reporting 8 CPUs and about 16 GiB: clone 3.0 s, install 17.2 s, typecheck 40.8 s. Cloudflare Sandbox completed all seven phases in 189.9 s on a sandbox reporting 8 CPUs and about 16 GiB: clone 5.9 s, install 75.0 s, typecheck 72.6 s. The workload is OpenCode's provider benchmark: clone, bun install and typecheck. Results are from ComputeSDK's run of 30 October 2026, one run each.
Which has stronger isolation, E2B or Cloudflare Sandbox?
Both use a microVM with its own kernel by default. E2B: Firecracker microVM. Cloudflare Sandbox: Firecracker microVM per instance, with your image running as a container inside it.
Can I self-host E2B or Cloudflare Sandbox?
E2B: Yes. The infrastructure is open source under Apache-2.0, with Terraform for Google Cloud, AWS and Azure, and a single-host option. Cloudflare Sandbox: No. The SDK is open source (Apache-2.0); the runtime is Cloudflare-hosted.
Is there an alternative to E2B and Cloudflare Sandbox that runs on my own hardware?
Yes. Hotcell is an open-source sandbox runtime (Apache-2.0) that runs Docker containers, Firecracker microVMs or Apple Virtualization microVMs on your own machines. Real API keys stay on the host, and each sandbox gets a short-lived, spend-capped token. Directionally Local sets it up together with the Autopilot coding agent harness with one command.