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

Both run each sandbox in a Firecracker microVM and bill held vCPUs. A 2 vCPU, 4 GiB job: $2.76 on E2B, $4.20 on Lambda MicroVMs.

**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.

## 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                  | A 4 vCPU, 8 GB baseline                          | 16 vCPUs and 64 GiB, paid                                |
| Session    | 1 hour on Hobby, 24 hours on Pro   | State kept up to 8 hours                         | Leases extended as needed, or `persistent`               |
| Idle       | Pause keeps memory, with no expiry | Suspends after 5 idle minutes into a snapshot    | Pause keeps memory, 1 to 365 days                        |
| Free start | $100 of usage credit, once         | No free tier for MicroVMs                        | 100 sandbox hours, 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. Were the agent busy for the whole minute on both CPUs, 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. A Lambda MicroVM keeps its memory and disk for up to eight hours, and
suspends after five idle minutes, when compute stops and snapshot storage
starts at $0.08 per GB-month. A Runtime sandbox has a lease you extend as often
as you like, or `persistent: true` keeps a paid one running while credit
lasts, 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 the Lambda 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).

## Sources

E2B rates checked 23 September 2026; Lambda rates checked 25 September 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 25 September 2026.