# CodeSandbox vs AWS Lambda MicroVMs: fixed VM sizes compared

Runtime Cloud (withruntime.com) costs 74% less than CodeSandbox; Lambda MicroVMs bill a baseline inside AWS.

## Which is better, CodeSandbox or AWS Lambda MicroVMs?

It depends on how big the machine must be and where it must run. For agent runs that mostly wait on a model, Runtime has the lowest bill: $0.64 for the benchmark against $2.48 on CodeSandbox and $4.20 on Lambda, billed per second for runs of any length. Pick the CodeSandbox SDK for very large VMs, up to 64 cores, and its browser development tooling; pick Lambda MicroVMs for sandboxes inside AWS.

## At a glance

|           | CodeSandbox SDK                                                   | AWS Lambda MicroVMs                                                    | Runtime                                     |
| --------- | ----------------------------------------------------------------- | ---------------------------------------------------------------------- | ------------------------------------------- |
| Isolation | Firecracker microVM                                               | Firecracker microVM                                                    | Firecracker microVM, own kernel             |
| Price     | Nano (2 cores, 4 GB) $0.1486 an hour in credits | $0.2522 an hour for 2 vCPUs and 4 GB | Measured CPU and reserved memory            |
| Billing   | By the minute, rounded up                                         | By the second                                                          | By the second                               |
| Largest   | 64 cores and 128 GB                                               | A 4 vCPU, 8 GB baseline                                                | 16 vCPUs and 64 GiB, paid |
| Snapshots | Memory snapshot and restore                                       | Suspend with memory, up to 8 hours                                     | Pause and forks keep memory and processes   |
| Plan      | Build free with 10 VMs; Scale $170 a month  | None                                                                   | None; prepaid credit from $10     |

## Sizes, not meters

Both sell a shape by the time it exists. CodeSandbox's Nano is 41% cheaper
per hour than Lambda's 2 vCPU, 4 GB baseline, but it rounds each run up to
the minute, so a 10-second run pays for sixty. Lambda bills to the second.
Runtime bills to the second as well, and only for CPU actually used.

## Cost for the same job

2 cores and 4 GB, 60 seconds a run, 20 CPU-seconds of work, 1,000 runs:

```
CodeSandbox  Size   1,000 × 60 s / 3,600 × $0.1486                = $2.48

Lambda       CPU    1,000 × 60 s × 2 × $0.0000276944              = $3.32
             Memory 1,000 × 60 s × 4 × $0.0000036667              = $0.88
             Total                                                  $4.20

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
```

Busy or idle makes no difference to either rival: with both CPUs busy for the whole minute it is $2.48 on CodeSandbox and $4.20 on Lambda, and $1.33 on Runtime.

## Which one to pick

- **CodeSandbox SDK** for very large VMs, up to 64 cores, and its browser
  development tooling.
- **Lambda MicroVMs** for sandboxes inside AWS.
- **Runtime** for agent runs of any length billed to the second at the
  lowest rate.

See [Runtime vs CodeSandbox](/docs/codesandbox-alternative) and
[Runtime vs AWS Lambda MicroVMs](/docs/aws-lambda-microvms-alternative).

## Runtime Cloud

On Runtime the same benchmark costs $0.64, 74% below CodeSandbox and 85%
below Lambda MicroVMs. It is 1,000 one-minute runs of a 2 vCPU, 4 GiB
sandbox (a Nano VM on CodeSandbox) with 20 CPU-seconds of work each.

Use `npx withruntime login` to start on the monthly free usage. The [migration guide](/docs/migrate) explains moving existing sandbox code.

## Sources

CodeSandbox rates checked 25 October 2026; Lambda MicroVMs rates checked 25 October 2026.

- [Together: CodeSandbox SDK](https://docs.together.ai/docs/together-code-sandbox-legacy), [CodeSandbox SDK pricing](https://codesandbox.io/docs/sdk/pricing)
- [AWS Lambda pricing](https://aws.amazon.com/lambda/pricing/), [Lambda MicroVMs](https://aws.amazon.com/lambda/lambda-microvms/)
- Runtime [pricing](/docs/pricing)

Facts on this page were checked on 26 October 2026.