Cloudflare Sandbox vs Northflank Northflank is 18% cheaper per agent run

Which is better, Cloudflare Sandbox or Northflank?

It depends on how much your sandboxes compute. For agents that mostly wait on a model, Runtime has the lowest bill: $0.64 for the job against $1.11 on Northflank and $1.35 on Cloudflare, and creating a sandbox is one API call. Pick Northflank if every CPU is busy all the time, where it costs less than Runtime, for L4, A100 or H100 GPUs, or to run in your own cloud account. Pick Cloudflare Sandbox for a Workers app that wants sandboxes near users.

At a glance

Cloudflare's Sandbox SDK is billed at Cloudflare Containers rates, which are used below.

Why is Northflank cheaper when Cloudflare bills only active CPU?

Because Cloudflare's memory rules cost more than Northflank's whole bill for CPU. Northflank charges $0.01667 per vCPU-hour for every vCPU a sandbox holds, so two vCPUs for a minute cost well under a cent whether they work or wait. Cloudflare charges only for CPU used, at $0.072 a vCPU-hour, but a 2 vCPU sandbox must be provisioned with at least 6 GiB of memory, billed for the whole run with its disk. In the example below Cloudflare's memory and disk alone come to $0.95, and Northflank's memory to $0.56.

Cloudflare wins only for sandboxes that barely compute: under about 8 of their 120 CPU-seconds in a one-minute run. Above that, Northflank is cheaper, and the gap grows with load.

Cost for the same job

Each of 1,000 runs holds 2 vCPU for 60 seconds and computes for 20 CPU-seconds. Northflank is priced with 4 GB and Runtime with 4 GiB. For Cloudflare the minimum of 3 GiB per vCPU means 6 GiB, and the disk is the 12 GB of Cloudflare's own example.

A month at 100,000 runs is $135.04 on Cloudflare, $111.10 on Northflank and $63.89 on Runtime. The busy case reverses the order: with both CPUs busy for the whole minute it is $1.11 on Northflank, $1.33 on Runtime and $3.35 on Cloudflare, so Northflank's low allocated rate wins there, the only such case here. Runtime stays below Northflank while a run keeps its CPUs busy for less than about 88 of 120 CPU-seconds, which is the usual case for agents that wait on a model. Cloudflare is priced as if each sandbox were destroyed at the end of its run, and plan fees, Workers requests, Durable Object time, storage, network and free allowances are omitted.

How much setup does each need?

Cloudflare's Sandbox SDK runs inside a Worker on the Workers Paid plan: a Sandbox export, a Durable Object binding and a containers entry, deployed with Wrangler and a local Docker build. Northflank creates each sandbox as a service with a deployment plan. On Runtime a sandbox is one call, and an agent connects by browser approval with no API key to copy:

Terminalprintf '%s\n' 'print(sum([125, 250, 375]))' > invoice.pynpx withruntime sandboxes run -- python3 - < invoice.py

Pythonfrom withruntime import Sandboxwith Sandbox.create() as box:    box.files.write("/workspace/invoice.py", "print(sum([125, 250, 375]))\n")    print(box.exec("python3 /workspace/invoice.py", check=True).stdout)

Which one to pick

For that last row Runtime is 42% below Northflank and 53% below Cloudflare, and its pause and forks keep memory and running processes. Northflank can also run in your own AWS, GCP or Azure account.

Porting from each

Cloudflare 0.x: getSandbox(env.Sandbox, name) becomes Sandbox.getOrCreate(name), sandbox.exec(cmd) becomes exec, and proxyToSandbox becomes box.previews.create(port). Northflank: where the code creates a sandbox service, create a Runtime sandbox; send commands with exec; and call stop() where the service was deleted.

The migration page holds one instruction a coding agent can follow to port the project on a branch and test it on the free usage. For Cloudflare users, credit you add within 30 days of signing up is matched, up to $1,000 in total. Read more in Runtime vs Cloudflare, Runtime vs Northflank, microVM vs container and gVisor.

Sources

Rates checked 25 October 2026.

• Cloudflare Containers pricing, Containers limits and instance types, Containers architecture
• Northflank pricing, Northflank sandboxes, Sandboxes on Northflank
• Runtime pricing

Facts on this page were checked on 26 October 2026.