# E2B vs AWS Lambda MicroVMs: pricing, sessions and limits

Runtime Cloud (withruntime.com) costs 77% less than E2B, which in turn costs less than Lambda MicroVMs.

## Which is better, E2B or AWS Lambda MicroVMs?

It depends on where the rest of your stack lives. For agents that wait on a
model, Runtime is the cheapest
of the three Firecracker options: $0.64 for this job, against
$2.76 on E2B and $4.20 on Lambda, and still the
lowest with both CPUs busy. Pick E2B to self-host later under Apache-2.0 or to
keep paused sandboxes with no expiry. Pick Lambda MicroVMs if everything else
is on AWS and you want IAM, VPC access and many regions.

## At a glance

|            | E2B                                       | AWS Lambda MicroVMs                                                       | Runtime                                                        |
| ---------- | ----------------------------------------- | ------------------------------------------------------------------------- | -------------------------------------------------------------- |
| Isolation  | Firecracker microVM, own kernel           | Firecracker microVM                                                       | Firecracker microVM, own kernel                                |
| CPU        | $0.0504 per allocated vCPU-hour  | $0.0997 per baseline vCPU-hour, billed by second | $0.025 per vCPU-hour of measured CPU, with a small floor |
| Memory     | $0.0162 per GiB-hour          | $0.0132 per GB-hour, 2 GB per vCPU            | $0.0075 per reserved GiB-hour                          |
| Largest    | 8 vCPUs and 8 GiB                         | 4 vCPUs and 8 GB at peak                                                  | 16 vCPUs and 64 GiB, paid                    |
| Session    | 1 hour on Hobby, 24 hours on Pro          | State kept up to 8 hours                                                  | No time limit: runs while it works, or `persistent`            |
| Idle       | Pause keeps memory, with no expiry        | Suspends into a snapshot after an idle time you set                       | Pause keeps memory while you have credit                       |
| Free start | $100 of usage credit, once | No free tier for MicroVMs                                                 | 100 free hours of a 1 GB machine in the first 30 days, no card             |

## Why is Lambda dearer than E2B here?

Lambda's memory rate is a little lower per unit, but its CPU is about twice E2B's: $0.0997 per vCPU-hour against $0.0504. For a 2 vCPU sandbox that is
$0.199 an hour of CPU on Lambda and $0.101 on E2B, whatever the code does.
Neither discounts a vCPU for sitting idle while the agent waits on its model.
Runtime does: waiting costs a floor of a twentieth of a vCPU.

## Cost for the same job

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

```
E2B       CPU    1,000 × 60 s / 3,600 × 2 × $0.0504            = $1.68
          Memory 1,000 × 60 s / 3,600 × 4 × $0.0162            = $1.08
          Total                                                  $2.76

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
```

At 100,000 runs a month that is $276.00 on E2B, $420.33 on Lambda MicroVMs and
$63.89 on Runtime. If the agent kept both CPUs busy for the whole minute, the job would cost
$1.33 on Runtime, still the lowest, with $2.76 on E2B and $4.20 on Lambda unchanged,
since both already bill every vCPU as if it worked.

## Sessions: one hour, eight hours, or as long as you like

E2B's free Hobby plan caps a session at an hour; Pro at $150 a month lifts it
to 24 hours. A Lambda MicroVM keeps its memory and disk for up to eight hours, and
suspends after an idle time you set, when compute stops and snapshot storage
starts at $0.08 per GB-month. A Runtime sandbox has no time limit: it runs while it
works, `persistent: true` keeps a paid one running even while idle, and a pause keeps its memory for as many days as you set, up to 365.

## Which one to pick

- **E2B** if you want to self-host later (its runtime is Apache-2.0) or keep
  paused sandboxes with no expiry.
- **Lambda MicroVMs** if everything else is already on AWS: IAM, VPC access
  through a network connector, and many regions.
- **Runtime** for agents that wait on models: the lowest bill of the three at
  any level of use, sandboxes up to 16 vCPUs and 64 GiB, and forks that copy a
  running machine. `withruntime/e2b` runs E2B code by changing one import.

See [Runtime vs E2B](/docs/e2b-alternative) and
[Runtime vs AWS Lambda MicroVMs](/docs/aws-lambda-microvms-alternative).

## Runtime Cloud

Runtime runs the same job for 77% less than E2B and 85% less than Lambda
MicroVMs. 1,000 one-minute runs of a 2 vCPU, 4 GiB sandbox cost $2.76 on
E2B, $4.20 on AWS Lambda MicroVMs and $0.64 on Runtime. All three use
Firecracker; only Runtime bills the CPU the code used instead of every vCPU
it holds.

Sign in with `npx withruntime login` and run the job on the free usage. E2B
code switches with one import line, as the [migration guide](/docs/migrate)
explains.

## Sources

E2B rates checked 25 October 2026; Lambda rates checked 25 October 2026.

- [E2B pricing](https://e2b.dev/pricing), [E2B sandbox persistence](https://docs.e2b.dev/sandbox/persistence)
- [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.