What is the best alternative to Northflank?
It depends on how hard your code keeps its CPUs busy. For agents that spend most of each run waiting on a model, Runtime has the lowest bill: $0.64 for the job below, against $1.11 on Northflank. A sandbox is one call. If your CPUs rarely rest, stay on Northflank: with both CPUs busy, it costs less than Runtime. Pick Fly Machines for 17 regions, and Modal for GPU sandboxes next to functions.
Why do teams look beyond Northflank?
Northflank runs services and databases, and its sandboxes are services too. Its allocated rates are the lowest in the table below. The reasons to move are about what an agent actually does:
- Agents mostly wait. Northflank bills the vCPUs and memory a sandbox holds for as long as it runs. An agent that spends 40 of every 60 seconds waiting for a model pays for idle CPUs. Runtime measures CPU, so waiting costs a floor of a twentieth of a vCPU.
- A sandbox is a service. Northflank creates each sandbox as a service
with a deployment plan.
Sandbox.create()on Runtime returns a running sandbox, with no service, project or plan to set up. - Memory costs more per unit. $0.00833 per GB-hour on Northflank, against $0.0075 per GiB-hour on Runtime. A GiB is about 7% larger than a GB.
- SSO is Enterprise. Northflank's plan table, read on 25 October 2026, marks SAML and OIDC sign-in, SCIM and audit logging for Enterprise. On Runtime, single sign-on, directory sync and the audit log are free on every account.
- State between steps. A paused Runtime sandbox wakes with its processes still running, kept while you have credit. A fork copies a running sandbox with its memory.
Which alternatives are cheapest?
Every provider runs the same job at list rates: 1,000 runs of a 2 vCPU, 4 GiB sandbox, 60 seconds apiece, with the code using 20 CPU-seconds of each run. Northflank's low allocated rates put it second, behind only Runtime. Pricing spells out each row. Plan fees, storage, network, credits and negotiated prices are left out.
| # | 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, the one you are replacing | 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 | 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, a user-space kernel | 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 |
microVM, with a container inside | Allocated CPUs while running | $5.33 |
Cost for the same job
The working for Runtime, Northflank, the next cheapest allocated VM (Fly Machines), and Modal, which, like Northflank, offers GPU sandboxes:
- 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 × $0.01667
- $0.556
- Memory
- 1,000 × 60 s / 3,600 × 4 × $0.00833
- $0.555
- Size
- 1,000 × 60 s / 3,600 × $0.0916704
- $1.53
- CPU
- 1,000 × 60 s × 1 core × $0.00003942
- $2.37
- Memory
- 1,000 × 60 s × 4 × $0.00000667
- $1.60
The comparison turns on how busy the code is. Kept busy for the whole minute on both CPUs, the job costs $1.33 on Runtime, $1.11 on Northflank, $1.53 on Machines, and $3.97 on Modal. This is the only case on this page where Northflank wins. Its allocated vCPU rate is below Runtime's measured one, so work that never lets the CPUs rest is cheaper there. Runtime stays cheaper until a run keeps its two vCPUs busy for about 88 of their 120 CPU-seconds, 73% of the time. When waiting, 100,000 runs a month cost $63.89 on Runtime and $111.10 on Northflank.
Where each alternative stands against Northflank
1. Cloudflare Sandbox: active CPU in 10 ms steps
$0.072 per vCPU-hour of active CPU, metered in 10 ms steps, with 3 GiB per vCPU at minimum. It runs from a Worker on the Workers Paid plan and starts near users across Cloudflare's network.
2. Fly Machines: the nearest billing model
Like Northflank, it bills a size while started. performance-2x with 4 GB is
$0.0916704 an hour in iad. Its performance vCPUs are whole cores held for the
Machine, in 17 regions.
3. Morph: live branching
$0.05 per MCU-hour, where an MCU is 1 vCPU, 4 GB of memory or 16 GB of disk. Infinibranch forks a running machine, memory and all, into hundreds of replicas.
4. Vercel Sandbox: made for Vercel apps
Firecracker at $0.128 per active CPU-hour and $0.0212 per GB-hour in iad1, in
19 regions, and up to 10,000 sandboxes at the same time on Pro.
5. CodeSandbox SDK: sizes by credit
The Nano VM (2 cores, 4 GB) is $0.1486 an hour in credits, rounded up to the minute. VMs go up to 64 cores and 128 GB.
6. E2B: self-hostable microVMs
$0.0504 per vCPU-hour and $0.0162 per GiB-hour. Its runtime is Apache-2.0, so it can run on your own servers, much as Northflank can run in your cloud.
7. Daytona: GPUs and Windows
The rates E2B charges, containers by default, GPU sandboxes and Windows machines in the US and the EU.
8. Blaxel: goes idle by itself
$0.0000115 per GB-second of active time, CPU included. Standby begins about 15 seconds after connections close, and a sandbox resumes in about 25 ms.
9. Fly Sprites: Fly.io's measured-CPU sandbox
$0.0385 per measured CPU-hour and $0.021875 per GB-hour of memory in use. A Sprite pauses itself and keeps a 100 GB disk.
10. Modal Sandboxes: gVisor with GPUs
gVisor isolation, as on Northflank's GPU sandboxes, at $0.1419 per physical core-hour on whichever is higher of request and use, next to Modal's functions.
11. Runloop: devboxes in your cloud
A container inside a microVM at $0.108 per CPU-hour and $0.0252 per GB-hour, plus disk. Like Northflank, it can deploy into your own cloud account.
Runtime Cloud
For an agent that spends its time waiting on a model, Runtime costs 42% less than Northflank, and a sandbox is one call. The 1,000 one-minute runs of a 2 vCPU, 4 GiB sandbox cost $0.64 on Runtime and $1.11 on Northflank. That is $47 a month saved at 100,000 runs, so Runtime is first in the table above. The gap comes from billing the CPU your code uses rather than every vCPU it holds. Rates were checked 25 October 2026.
Each sandbox is a Firecracker microVM with its own kernel. It is charged $0.025 per
vCPU-hour of measured CPU, never under a twentieth of a vCPU, and $0.0075 per
reserved GiB-hour. It is shaped around agents. Sign-in is a browser approval
rather than a pasted key. Read-only keys, a daily spending limit per key,
and maxTotalCostMicros on each sandbox keep one inside its budget.
To find out where your own work lands, start free with npx withruntime login
and run it. The migration guide and the steps below move a
Northflank sandbox setup across.
How to switch from Northflank
There is no service or deployment plan to translate. A sandbox is created, used and stopped, in TypeScript or Python:
TypeScriptimport { Sandbox } from "withruntime";const box = await Sandbox.create();try { await box.files.write("/workspace/invoice.py", "print(sum([125, 250, 375]))\n"); console.log((await box.exec("python3 /workspace/invoice.py", { check: true })).stdout);} finally { await box.stop();}Pythonfrom withruntime import Sandboxwith Sandbox.create() as box: box.files.write("/workspace/invoice.py", "print(sum([125, 250, 375]))\n") print(box.exec("python3 /workspace/invoice.py", check=True).stdout)To see which side of the busy line your own work falls on, run it on Runtime for a few days, then price the same sandboxes at Northflank's published rates:
Terminalnpx withruntime compare --from northflankA coding agent can also run the whole move. Paste the instruction from migration, and it changes the project on a branch, tests it on the free usage, and reports the monthly saving. For where measured CPU saves most, see coding agent sandbox and run untrusted LLM code.
Sources
Fly.io prices were checked 25 October 2026.
Rival rates were checked 25 October 2026. Northflank's pricing page was read again on 26 October 2026.
Facts on this page were checked on 26 October 2026.