# Vercel Sandbox vs AWS Lambda MicroVMs: two clouds' Firecracker sandboxes

Runtime Cloud (withruntime.com) costs 70% less than either. Vercel bills active CPU, and Lambda bills a baseline.

## Which is better, Vercel Sandbox or AWS Lambda MicroVMs?

It depends on which cloud your app lives in. For agents that mostly wait on a
model, Runtime bills active CPU as Vercel does, at a lower rate. The benchmark costs $0.64 on Runtime,
against $2.12 on Vercel and $4.20 on Lambda. Runtime
keeps memory across pauses, and it runs Vercel Sandbox code after one import
change. Pick Vercel Sandbox for an app hosted on Vercel, or for a choice of 19
regions. Pick Lambda MicroVMs for workloads that must stay inside an AWS VPC.

## At a glance

|           | Vercel Sandbox                                       | AWS Lambda MicroVMs                                     | Runtime                                                        |
| --------- | ---------------------------------------------------- | ------------------------------------------------------- | -------------------------------------------------------------- |
| Isolation | Firecracker microVM, own kernel                      | Firecracker microVM                                     | Firecracker microVM, own kernel                                |
| CPU       | $0.128 per active CPU-hour, `iad1`      | $0.0997 per baseline vCPU-hour | $0.025 per vCPU-hour of measured CPU, with a small floor |
| Memory    | $0.0212 per provisioned GB-hour       | $0.0132 per GB-hour         | $0.0075 per reserved GiB-hour                          |
| Largest   | 8 vCPUs and 16 GB on Pro; 32 and 64 GB on Enterprise | A 4 vCPU, 8 GB baseline                                 | 16 vCPUs and 64 GiB, paid                    |
| Idle      | Stop keeps the filesystem; processes start again     | Suspend keeps memory and disk, up to 8 hours            | Pause keeps memory and processes while you have credit         |
| Regions   | 19                                                   | AWS regions                                             | One US region                                                  |

## Active CPU against the baseline

Vercel and Runtime both charge CPU only while it works. That is why Vercel
beats Lambda on a waiting agent, even though its CPU rate is the highest of the
three. Lambda charges its baseline for every second a MicroVM is up. The order
flips when the work gets busy, because then Vercel's $0.128 rate bites.

## Cost for the same job

1,000 runs of 60 seconds on 2 vCPU and 4 GiB (4 GB on both rivals), 20
CPU-seconds of work each:

```
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

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
```

That is $212.44, $420.33 and $63.89 for a month of 100,000 runs. With both CPUs busy for the whole minute, the job costs $5.68 on Vercel, $4.20 on Lambda and $1.33 on Runtime. Lambda becomes cheaper than Vercel, and Runtime stays cheapest.

## Which one to pick

- **Vercel Sandbox** for apps already on Vercel, in any of 19 regions.
- **Lambda MicroVMs** for workloads that live inside an AWS VPC.
- **Runtime** for active-CPU billing at 80% below Vercel's rate, memory kept
  across pauses, and `withruntime/vercel` for Vercel Sandbox code after one
  import change.

See [Runtime vs Vercel Sandbox](/docs/vercel-sandbox-alternative) and
[Runtime vs AWS Lambda MicroVMs](/docs/aws-lambda-microvms-alternative).

## Runtime Cloud

Runtime runs the benchmark for 70% less than Vercel and 85% less than Lambda. The
benchmark is 1,000 one-minute runs of a 2 vCPU, 4 GiB sandbox that computes
for 20 CPU-seconds of each minute: $2.12 on Vercel Sandbox, $4.20 on AWS Lambda
MicroVMs, $0.64 on Runtime. All three run Firecracker.

Start free with `npx withruntime login`. For Vercel Sandbox or Lambda code, the
[migration guide](/docs/migrate) lists what changes.

## Sources

Vercel rates checked 25 October 2026; Lambda rates checked 25 October 2026.

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