What is the best alternative to E2B?
It depends on how your agent spends its time and what else it needs. For agents that mostly wait on a model, Runtime has the lowest bill: $0.64 for the job below against $2.76 on E2B, because it bills measured CPU, not held vCPUs. Each sandbox is still a Firecracker microVM, and a pause keeps memory and processes. Pick Northflank to run sandboxes inside your own cloud account, Cloudflare Sandbox if your app lives on Workers, and Daytona for GPUs or Windows.
Why do teams leave E2B?
E2B and Runtime isolate code the same way, so the reasons to move are about the bill and the plan rather than the security model:
- Held vCPUs are billed while the agent thinks. E2B's $0.0504 per vCPU-hour applies to every allocated vCPU for the whole life of the sandbox. In the example, 40 of each run's 60 seconds pass waiting on a model, and E2B bills both vCPUs through all of them.
- Memory costs more than twice as much. E2B lists $0.0162 per GiB-hour; Runtime lists $0.0075.
- Long sessions need Pro. A Hobby sandbox lives at most an hour, and 24 hours needs Pro at $150 a month. A Runtime sandbox has no time limit: it runs while it works, on prepaid credit from $10 with no plan.
- Concurrency comes in tiers. E2B's pricing page, read on 26 October 2026, allows 20 concurrent sandboxes on Hobby and 100 on Pro, with paid add-ons for 600 or 1,100. A paid Runtime account runs 100 concurrent sandboxes with no plan fee, and support raises the limit when you send your numbers.
- Enterprise features wait for Enterprise. E2B's enterprise page, read on 25 October 2026, sends OpenTelemetry metrics and logs only on that plan and lists SSO, SCIM and role-based access as planned. Runtime's OpenTelemetry export and single sign-on are free on every account.
- Agents carry an API key. Runtime signs an agent in with a browser approval instead, so no key ends up in a prompt or a config file.
Which alternatives are cheapest?
Every row prices one job at list rates: 1,000 runs, each 60 seconds long on a 2 vCPU, 4 GiB sandbox, with 20 CPU-seconds of real work per run. For an E2B user, the column to read is the last one against E2B's row. The arithmetic behind each figure is on pricing; plan fees, storage, network, credits and negotiated deals stay out of it.
| # | Provider | Isolation | CPU billed on | 1,000 runs |
|---|---|---|---|---|
| 1 | Runtime Cloud | Firecracker microVM, own kernel | Measured CPU, with a small floor | $0.64 |
| 2 | Northflank | microVMs for CPU work, gVisor for GPU work | Allocated vCPUs | $1.11 |
| 3 | Cloudflare Sandbox (2 vCPU, 6 GiB, 12 GB disk) | A container in its own VM | Active CPU | $1.35 |
| 4 | Prime Sandboxes (5 GiB disk) | microVM, own guest kernel | Allocated vCPUs while running | $1.52 |
| 5 | Fly Machines, performance-2x with 4 GB |
Firecracker microVM | The machine's size while started | $1.53 |
| 6 | Morph, 2 MCUs | Full virtual machines | The machine's size in MCUs | $1.67 |
| 7 | Vercel Sandbox, iad1 (4 GB) |
Firecracker microVM, own kernel | Active CPU | $2.12 |
| 8 | Freestyle (32 GiB disk) | Full Linux virtual machines | Allocated vCPUs | $2.25 |
| 9 | Fly Sprites (4 GB in use) | Firecracker microVM | Measured CPU | $2.40 |
| 10 | CodeSandbox SDK, a Nano VM | Firecracker microVM | The VM's size, by the minute rounded up | $2.48 |
| 11 | E2B (the one you are replacing) | Firecracker microVM, own kernel | Allocated vCPUs | $2.76 |
| 12 | Daytona | Containers by default; VM class separate | Allocated vCPUs | $2.76 |
| 13 | Blaxel (4 GB) | Lightweight virtual machines | Included with memory, active time | $3.45 |
| 14 | Modal Sandboxes (1 physical core) | gVisor, or a VM on request | Requested or used, whichever is higher | $3.97 |
| 15 | AWS Lambda MicroVMs, Arm | Firecracker microVM | Baseline vCPUs while running | $4.20 |
| 16 | Runloop, a MEDIUM devbox |
Hardware-isolated microVM | Allocated CPUs while running | $5.33 |
Cost for the same job
The lines for Runtime, E2B, Daytona (which publishes E2B's exact rates) and Vercel (the other Firecracker host that bills active CPU):
- CPU
- 1,000 × 20 s / 3,600 × $0.025
- $0.14
- Memory
- 1,000 × 60 s / 3,600 × 4 × $0.0075
- $0.50
- CPU
- 1,000 × 60 s / 3,600 × 2 × $0.0504
- $1.68
- Memory
- 1,000 × 60 s / 3,600 × 4 × $0.0162
- $1.08
- CPU
- 1,000 × 60 s / 3,600 × 2 × $0.0504
- $1.68
- Memory
- 1,000 × 60 s / 3,600 × 4 × $0.0162
- $1.08
- CPU
- 1,000 × 20 s / 3,600 × $0.128
- $0.71
- Memory
- 1,000 × 60 s / 3,600 × 4 × $0.0212
- $1.41
Had the agent kept both CPUs busy for the whole minute, the job would come to $1.33 on Runtime, $2.76 on E2B, $2.76 on Daytona and $5.68 on Vercel. E2B's figure stays put because it already bills each vCPU as if it were working; Runtime's rises and still ends up 52% below it. At 100,000 runs a month, the waiting job is $63.89 on Runtime and $276.00 on E2B.
What each alternative offers an E2B user
1. Northflank: E2B's billing model with smaller numbers
Northflank charges $0.01667 per allocated vCPU-hour, about a third of E2B's, and $0.00833 per GB-hour, and it is the one provider here that costs less than Runtime when both CPUs stay busy, $1.11 to $1.33. Each sandbox is a service with a deployment plan, and it can run inside your own AWS, GCP or Azure account.
2. Cloudflare Sandbox: when the app already lives on Workers
Active CPU at $0.072 per vCPU-hour, but at least 3 GiB per vCPU, so this job is priced at 6 GiB, and the Workers Paid plan from $5 a month. Where an E2B pause holds state, Cloudflare's public-beta snapshots restore saved files while memory and processes restart.
3. Fly Machines: a whole machine for less than E2B's parts
The same Firecracker underneath, billed by size for each second a Machine is
started. A performance-2x with 4 GB costs $0.0916704 an hour in iad, against
$0.1656 an hour for 2 vCPUs and 4 GiB at E2B's rates, so it wins busy or idle.
There are 17 regions to pick from; the root disk does not survive the Machine.
4. Morph: branch a sandbox while it runs
This job fits in 2 MCUs at $0.05 each, $0.10 an hour. Infinibranch copies a running machine, memory included, into hundreds of replicas, for agents that try several paths from one starting state.
5. Vercel Sandbox: active CPU at a high rate
Firecracker again, billing only active CPU, but at $0.128 per CPU-hour, so it beats E2B only while the agent waits: $2.12 to $2.76, then $5.68 once both CPUs work. It runs in 19 regions, 10,000 concurrent sandboxes on Pro.
6. CodeSandbox SDK: a fixed VM, rounded to the minute
A Nano VM, 2 cores and 4 GB, costs $0.1486 an hour in credits, a little under E2B's price for the same shape. Each run is billed by the minute, rounded up, and more than 10 concurrent VMs needs the Scale plan at $170 a month.
7. Daytona: the same meter, plus GPUs and Windows
Daytona publishes E2B's rates to the fourth decimal, so moving saves nothing. It adds GPU sandboxes, Windows machines, US and EU regions and $200 of free compute, with a container as the default sandbox.
8. Blaxel: one memory meter, standby built in
Active memory at $0.0000115 per GB-second, with CPU included, lands this job at $3.45, against E2B's $2.76. A sandbox drops to standby when its connections close and resumes in about 25 ms.
9. Fly Sprites: measured CPU, costly memory
Sprites meter CPU the way Runtime does, at $0.0385 per CPU-hour, but charge $0.021875 per GB-hour for memory in use, which puts this job above E2B at $2.40. A Sprite pauses on its own and keeps a 100 GB disk.
10. Modal Sandboxes: GPUs next to functions
gVisor, a user-space kernel, or a VM on request, and CPU billed on the larger of request and use at $0.1419 per physical core-hour: $3.97 for the job. The draw is GPUs beside Modal's functions.
11. Runloop: evaluation tooling at a premium
$0.108 per CPU-hour and $0.0252 per GB-hour plus disk, almost double E2B at $5.33, in return for tools to evaluate models on your own workload.
Runtime Cloud
Leaving E2B for Runtime keeps the Firecracker microVM and cuts the bill by 77%. The job above, 1,000 one-minute runs on a 2 vCPU, 4 GiB sandbox, is $0.64 on Runtime and $2.76 on E2B, a difference of $212 a month at 100,000 runs, so Runtime is first in the table above. E2B charges for every vCPU a sandbox holds; Runtime charges for the CPU time the code actually burns. Rates checked 25 October 2026.
Each sandbox is a Firecracker microVM with its own kernel, as on E2B, but the
CPU meter counts what the code consumed: $0.025 per vCPU-hour, never below a twentieth of a vCPU, plus $0.0075 per reserved GiB-hour. A pause keeps memory
and running processes, as E2B's does, while you have credit at $0.08 per GB a
month. The withruntime/e2b package takes E2B code with only the import
changed.
Start free with npx withruntime login. The switch below is one import, and
the migration guide can hand the rest of the port to your
coding agent.
How to switch from E2B
Install Runtime's SDK, version 0.11.2 or later (Python 0.11.1), and point the
import at its E2B layer. Authenticate with RUNTIME_API_KEY or a one-time
npx withruntime login:
TypeScriptimport { Sandbox } from "withruntime/e2b"; // was: from "e2b"Pythonfrom withruntime.e2b import Sandbox # was: from e2b import SandboxThe code interpreter has its own drop-ins, withruntime/e2b/code-interpreter
and withruntime.e2b.code_interpreter. Where a call has no direct match, such
as E2B's MCP gateway, workload identity or a files-only pause, it throws
NotSupportedError before doing anything and says which Runtime feature to use.
To hand the move off, paste the single instruction from migration into your coding agent. It ports the project on a branch, runs it without credit and reports the monthly difference. Credit you add within 30 days of signing up is matched, up to $1,000 in total. For closer looks, read E2B vs Daytona, E2B vs Modal, E2B vs Vercel Sandbox or price your own workload in the E2B pricing calculator.
Sources
Cloudflare sandbox lifetime, snapshot behavior checked 25 October 2026. Rival rates checked 25 October 2026. E2B's pricing page was read again on 26 October 2026 for its plan limits.
Runtime pricing and the E2B comparison
Facts on this page were checked on 26 October 2026.