E2B vs Cloudflare Sandbox Cloudflare 51% cheaper if agents wait, E2B 18% if busy

Which is better, E2B or Cloudflare Sandbox?

It depends on whether your app already runs on Workers. For agents that wait on a model, Runtime has the lowest bill: $0.64 for this job, against $1.35 on Cloudflare and $2.76 on E2B. It meters CPU in use like Cloudflare, at a lower rate, and needs no platform around it. Pick E2B for a runtime you host yourself or pauses that never expire. Pick Cloudflare Sandbox to keep sandboxes on the same account, bill and bindings as your Workers.

At a glance

The Cloudflare figures are Cloudflare Containers rates, which is what the Sandbox SDK runs on and is billed as.

Which is cheaper, E2B or Cloudflare?

For a waiting agent, Cloudflare. It meters CPU only while the code runs, $0.000020 per vCPU-second, and its memory is cheaper per GiB than E2B's. E2B charges for every allocated vCPU from start to stop. Cloudflare's cost comes from its shapes: a custom size needs at least 3 GiB per vCPU, so 2 vCPUs carry 6 GiB, and provisioned disk is billed on top.

That fixed part is about a third of E2B's hourly price, so Cloudflare stays cheaper until the code averages around 1.5 busy CPUs out of 2, some 90 CPU-seconds a minute. At full load E2B wins, $2.76 against $3.35. Runtime meters CPU at $0.025 a vCPU-hour, 65% below Cloudflare's $0.072, with memory set apart from vCPUs, and is below both at any load.

Cost for the same job

The case priced: 1,000 runs on 2 vCPU, 60 seconds each, 20 CPU-seconds of work per run. E2B and Runtime have 4 GiB. Cloudflare's smallest custom 2 vCPU shape has 6 GiB and is given 12 GB of disk, the disk of Cloudflare's 6 GiB standard-2 type.

That is $276.00 on E2B, $135.04 on Cloudflare and $63.89 on Runtime over 100,000 runs in a month. With both CPUs busy for the whole minute, it is $1.33 on Runtime, $2.76 on E2B and $3.35 on Cloudflare. Cloudflare is priced as if each sandbox were destroyed after its run. Plan fees, Workers requests, Durable Object time, network and free credit are left out.

What happens to an idle sandbox?

A paused E2B sandbox keeps its files, memory and running processes, with no expiry. Cloudflare's public-beta filesystem snapshots restore saved files, but memory and processes restart. A snapshot expires 30 days after creation or last restore. A paused Runtime sandbox keeps files, memory and running processes while you have credit, and wakes on the next request. See how to pause and resume a sandbox.

Which one to pick

• E2B, for a microVM API that any backend can call, paused sandboxes that never expire, or an Apache-2.0 runtime you can host yourself.
• Cloudflare Sandbox, for an app that already runs on Workers and wants its sandboxes on the same account, bill and bindings, near its users.
• Runtime, for CPU billed by use at 65% below Cloudflare's rate, memory sized to the job, a pause that keeps memory and processes, and an API that needs no platform around it.

Moving to Runtime

E2B code changes one import:

TypeScriptimport { Sandbox } from "withruntime/e2b"; // was: from "e2b"

Pythonfrom withruntime.e2b import Sandbox  # was: from e2b import Sandbox

Cloudflare 0.x code maps call for call and can then run on any server: getSandbox(env.Sandbox, name) is Sandbox.getOrCreate(name), sandbox.exec(cmd) is exec, and proxyToSandbox is box.previews.create(port). An app that stays on Workers can still call Runtime from the Worker, with SDK 0.4.0 or later and the nodejs_compat flag; the sample is in Runtime vs Cloudflare.

TypeScriptimport { Sandbox } from "withruntime";const box = await Sandbox.create();try {  await box.files.write("/workspace/invoice.py", "print(sum([125, 250, 375]))\n");  console.log((await box.exec("python3 /workspace/invoice.py", { check: true })).stdout);} finally {  await box.stop();}

Credit you add within 30 days of signing up is matched, up to $1,000 in total. A coding agent can handle the port from the one instruction in migration, on a branch and on the free usage. For E2B in depth, see Runtime vs E2B.

Sources

• Cloudflare sandbox lifetime, snapshot behavior checked 25 October 2026. E2B and Cloudflare Containers pricing pages rechecked 25 October 2026; the rest checked 25 October 2026.

• E2B pricing, E2B sandbox persistence

• Cloudflare Containers pricing, Containers limits and instance types, Containers architecture, Sandbox lifecycle, Sandbox backup and restore

• Runtime pricing

Facts on this page were checked on 26 October 2026.