# Runtime vs Vercel Sandbox

Runtime and Vercel Sandbox both use Firecracker microVMs and bill active CPU; Runtime charges less, and a pause keeps memory.

This page compares the two for teams looking for a Vercel Sandbox alternative.
Facts about Vercel come from its public pricing and documentation, checked
22 September 2026, at the rates of its default `iad1` region; check the links at
the end before relying on them. Equal vCPU counts do not prove equal
performance, and the two services have not been benchmarked against each other.

## At a glance

|                 | Runtime                                              | Vercel Sandbox                                       |
| --------------- | ---------------------------------------------------- | ---------------------------------------------------- |
| Isolation       | Firecracker microVM, own kernel                      | Firecracker microVM, own kernel                      |
| CPU billing     | $0.025 per active vCPU-hour, with a small floor      | $0.128 per active CPU-hour                           |
| Memory billing  | $0.0075 per reserved GiB-hour                        | $0.0212 per provisioned GB-hour                      |
| Plan            | None; prepaid credit from $10                        | Hobby allowance free; usage beyond it needs Pro      |
| Free start      | 20 sandbox hours, no card                            | 5 active CPU-hours and 420 GB-hours a month on Hobby |
| Session length  | Leases of up to an hour, extended as often as needed | 45 minutes on Hobby, 24 hours on Pro                 |
| Stop and resume | Pause keeps files and memory                         | Stop keeps the filesystem; processes start again     |
| Regions         | One                                                  | 19                                                   |

## Cost for the same job

Take 1,000 runs of a 2 vCPU sandbox with 4 GiB on Runtime and 4 GB on Vercel.
Each run lasts 60 seconds and keeps the CPU busy for 20 CPU-seconds, which is
typical of an agent that spends most of its time waiting for a model.

```
Runtime  CPU    1,000 × 20 s / 3,600 × $0.025      = $0.14
         Memory 1,000 × 60 s / 3,600 × 4 × $0.0075 = $0.50
         Total                                        $0.64

Vercel   CPU    1,000 × 20 s / 3,600 × $0.128      = $0.71
         Memory 1,000 × 60 s / 3,600 × 4 × $0.0212 = $1.41
         Total                                        $2.12
```

Both bill CPU by use, so the gap holds as a workload gets busier: with both
CPUs busy for the whole minute, the same job costs $1.33 on Runtime and $5.68 on
Vercel. A GiB is about 7% larger than a GB, so Runtime's memory figure covers
slightly more. Creations, network, storage, plan fees, taxes and free
allowances are excluded from both. See [pricing](./pricing) for Runtime's terms.

## Where Vercel Sandbox is stronger

- **Regions and scale.** Vercel runs sandboxes in 19 regions, with up to 10,000
  at once on Pro. Runtime runs in one region.
- **Size.** Enterprise sandboxes go up to 32 vCPUs and 64 GB.
- **Persistence.** Vercel sandboxes save their filesystem on every stop by
  default, and Drives add persistent storage that sandboxes can share.
- **Platform.** If your application already runs on Vercel, sandboxes share its
  account, billing and observability, and Vercel reports SOC 2 Type II. Runtime
  has not completed an outside security audit.
- **Snapshots.** Runtime's are paused while an issue is fixed; build a
  [custom image](./javascript#custom-images) to start many sandboxes from one
  setup.

## Where Runtime is stronger

- **Price.** Active CPU costs about a fifth as much, and memory about a third.
- **Memory survives a pause.** A paused Runtime sandbox wakes with its processes
  still running. See [pricing](./pricing) for paused storage.
- **Setup by the agent.** An agent runs `npx withruntime run --trial -- ...`,
  shows you a link, and starts work once you approve it in the browser. No API
  key is copied into a prompt or a config file, and the [MCP server](./mcp)
  reuses the same connection.
- **No platform to join.** Runtime needs no hosting plan or project; prepaid
  credit is the whole account.

## Moving from Vercel Sandbox

Vercel Sandbox:

```js
import { Sandbox } from "@vercel/sandbox";
const sandbox = await Sandbox.create();
const command = await sandbox.runCommand("echo", ["hello"]);
console.log(await command.stdout());
await sandbox.stop();
```

Runtime:

```ts
import { Sandbox } from "withruntime";
const box = await Sandbox.create({ funding: "trial" });
try {
  console.log((await box.exec("echo hello", { check: true })).stdout);
} finally {
  await box.stop();
}
```

To have a coding agent make the switch, test it and compare costs on your own
workload, give it the prompt in [migration](./migrate). Keep Vercel Sandbox
available until the same job passes on both.

## Sources

- [Vercel Sandbox pricing and quotas](https://vercel.com/docs/sandbox/pricing)
- [Understanding Vercel Sandboxes](https://vercel.com/docs/sandbox/concepts)
- Runtime [pricing](./pricing), [security](./security) and [products](./products)