Blaxel vs Northflank
Both run each sandbox in a microVM with its own kernel. Blaxel is built to sleep in seconds and wake in under 25 ms with its memory intact, while Northflank is a broad platform with GPUs, regions around the world and the option to run in your own cloud.
The companies and products
Blaxel
Blaxel is a San Francisco company that runs cloud infrastructure for AI agents, and since September 2026 it is part of Baseten.
You get sandboxes, batch jobs, MCP server hosting and a model gateway. Each sandbox is a Firecracker microVM with its own kernel that drops to standby when nothing is connected and resumes in under 25 ms with its memory and running processes. It is built for agent products that start many sandboxes and want them asleep most of the time.
- Headquarters
- San Francisco, founded 2024
Northflank
Northflank is a London developer platform for running services, jobs and databases on Kubernetes, and Sandboxes is its product for running untrusted code.
A Northflank sandbox is a container image deployed as a service: CPU sandboxes run in Kata microVMs with their own kernel, and GPU sandboxes run under gVisor. You create and drive them from the JavaScript or Python SDK, the CLI or the dashboard, on Northflank's cloud or inside your own. It suits teams that already want one platform for apps, databases, GPUs and sandboxes.
Which use cases each one fits
For each use case, Battleships prices every sandbox provider on the same workload and sorts them from the cheapest monthly bill up. “10th cheapest of 367” means 9 of the other 366 providers run that workload, with every feature it needs, for less. “With limits” means the provider runs it but misses something, so it is listed after every full match. Open a use case for its whole ranking and what each provider misses.
| Use case and its workload | Blaxel: price rank | Northflank: price rank | bochka: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month Blaxel fits as is, while on Northflank only attached volumes survive a pause, and bochka keeps the whole disk and adds /dev/kvm. | 10th cheapest of 367 $2,373 a month | 159th of 367, with limits $1,477 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB | 12th cheapest of 366 $2,832 a month | 173rd of 366, with limits $1,365 a month | 5th cheapest of 366 $657 a month |
| Code interpreter bursts 100 at once · 1 vCPU / 2 GB · 200,000 sessions of 1 min a month Short runs suit both: Blaxel sleeps right away and wakes in milliseconds, and Northflank has small per-second plans from a tenth of a vCPU. | 14th cheapest of 345 $144 a month | 84th of 345, with limits $115 a month | 186th of 345, with limits $2,000 a month |
| Sandboxes for your users 300 at once · 2 vCPU / 4 GB · 30,000 sessions of 23 min a month Blaxel's self-serve tiers stop at 200 at once and Northflank does not publish its limit, while bochka fits 300 users at once on a self-serve plan. | 101st of 361, with limits $926 a month | 89th of 361, with limits $815 a month | Cheapest of 361 $209 a month |
| RL rollouts 1,000 at once · 2 vCPU / 4 GB · 1,000,000 sessions of 3 min a month | 77th of 360, with limits $4,378 a month | 342nd of 360, with limits $1,762 a month | 34th of 360, with limits $2,000 a month |
| Agent evals 250 at once · 4 vCPU / 8 GB · 15,000 sessions of 20 min a month | 136th of 364, with limits $704 a month | 134th of 364, with limits $689 a month | 10th cheapest of 364 $200 a month |
| CI runners 40 at once · 8 vCPU / 16 GB · 6,000 sessions of 12 min a month | 57th cheapest of 377 $431 a month | 38th cheapest of 377 $352 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB Northflank gives you SSH and Blaxel does not, but neither keeps the whole disk on a stop the way bochka does. | 265th of 368, with limits $114 a month | 151st of 368, with limits $59 a month | 18th cheapest of 368 $26 a month |
| Computer-use agents 50 at once · 4 vCPU / 8 GB · 20,000 sessions of 15 min a month Blaxel can run a desktop and a browser, Northflank sandboxes are headless, and bochka streams a 60fps desktop you can embed in your app. | 14th cheapest of 369 $634 a month | 151st of 369, with limits $371 a month | 6th cheapest of 369 $200 a month |
| Browser-use agents 50 at once · 2 vCPU / 4 GB · 30,000 sessions of 10 min a month Blaxel can run a browser in its sandboxes, while on Northflank you install and run one in your own image. | 16th cheapest of 367 $317 a month | 200th of 367, with limits $194 a month | 7th cheapest of 367 $200 a month |
| Scraping & bots (startup scale) 50 at once · 1 vCPU / 2 GB · 100,000 sessions of 3 min a month | 16th cheapest of 346 $215 a month | 196th of 346, with limits $117 a month | 6th cheapest of 346 $90 a month |
| Mass scraping & bots (undetectable) 1,000 at once · 1 vCPU / 2 GB · 3,000,000 sessions of 2 min a month | 147th of 338, with limits $4,292 a month | 83rd of 338, with limits $2,049 a month | 71st of 338, with limits $1,800 a month |
| Parallel red teaming 200 at once · 2 vCPU / 4 GB · 5,000 sessions of 30 min a month Blaxel adds domain, method and path rules on the provider side, and bochka gives root with raw TCP and nftables inside the VM. | 3rd cheapest of 360 $217 a month | 141st of 360, with limits $99 a month | 2nd cheapest of 360 $200 a month |
| GPU eval jobs 10 at once · 8 vCPU / 32 GB · 500 sessions of 30 min a month Northflank is the only one of the three with GPU sandboxes, from L4 to H100 and up. | Can't run it | 4th cheapest of 98 $693 a month | Can't run it |
| macOS agents 5 at once · 4 vCPU / 8 GB · 1,000 sessions of 20 min a month | Can't run it | Can't run it | Can't run it |
Key features
| Feature | Blaxel | Northflank | bochka |
|---|---|---|---|
| Isolation | Firecracker microVM with its own kernel | Kata microVM with its own kernel for CPU; gVisor for GPU | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| Sleep when idle | Standby a few seconds after the last connection; wakes in under 25 ms with memory and processes | No idle auto-pause; bills the full plan until you pause it | No idle auto-stop; a stopped sandbox costs nothing and keeps its disk, and resume boots the VM again |
| Disk | Files live in memory (about half the RAM); one block volume can be attached at creation | Only attached volumes survive a pause, and they bill while paused; the rest of the disk resets | A real disk that stays, saved every minute and on stop |
| Fork and snapshots | Fork with memory and running processes (private preview) | Opt-in filesystem snapshots of a running sandbox, restored into a new one | Automatic disk snapshots; fork a running sandbox |
| Nested virtualization | No: Firecracker guests do not get /dev/kvm | Not documented inside a sandbox | Yes: /dev/kvm, so Android emulators and VMs run inside |
| Shell access | Root, terminal through the bl connect command, no native SSH | SSH, browser terminal or SDK | Real SSH, root and systemd |
| Desktop and browser | Desktop and browser can run in a sandbox | Headless; you build a desktop and browser into your image | 60fps Linux desktop, Chromium and computer use built in |
| Coding agents | Claude Code image you drive from its terminal or your own harness | Harnesses with Claude Code, Codex, Cursor, OpenCode or Pi, reached through a terminal or SSH | Seven agents preinstalled, with a prompt, steer and events API |
| Keeping API keys out | Proxy fills secrets into outbound HTTPS requests (public preview) | Header injection for listed hosts in the network policy API | Credentials proxy for model providers and any HTTPS API; switch to another account when credits run out |
| Inbound traffic | Preview URL per port, public or token-protected; no raw TCP or public IP | HTTPS ports on a code.run domain, private by default; public TCP and UDP need a separate load balancer | HTTPS URLs for up to 50 ports, token-protected by default; raw TCP; own IPv4 or IPv6 |
| Outbound rules | Domain allow and deny lists, method and path rules, static egress IPs | Network policies with allow lists by IP, CIDR or domain, documented for your own cluster | Open internet; filter inside the VM with nftables |
| GPUs | No | L4, A100, H100, RTX PRO 6000 and more | No |
| Regions | Oregon, North Virginia, London, Frankfurt | US, Canada, Brazil, UK, EU, Switzerland, Asia, Australia and South Africa | EU only: Germany, Finland, France |
| Your own cloud | Bring your own metal on a custom quote | Run on AWS, GCP, Azure and others, or the control plane in your VPC on Enterprise | No |
Every feature Battleships tracks (43)
| Feature | Blaxel | Northflank | bochka |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | Yes | Yes |
| Nested virtualization | No | No | Yes |
| Root | Yes | Not published | Yes |
| Systemd | No | Not published | Yes |
| Desktop GUI | Yes | No | Yes |
| Browser | Yes | No | Yes |
| Computer-use API | Yes | No | Yes |
| SSH | No | Yes | Yes |
| Persistent disk | Yes | Yes | Yes |
| Pause/resume | Yes | Yes | Yes |
| Automatic snapshots | Yes | Yes | Yes |
| Fork/clone | Yes | Yes | Yes |
| Live fork (no pause) | Yes | Yes | Yes |
| Memory fork | Yes | No | No |
| Custom image (Docker or snapshot) | Yes | Yes | Yes |
| ≥24 h sessions | Yes | Yes | Yes |
| Idle auto-stop | Yes | No | No |
| Wake on request | Yes | No | No |
| HTTPS preview URLs | Yes | Yes | Yes |
| Raw TCP inbound | No | Yes | Yes |
| Public IPv4 | No | No | No |
| Egress allowlist | Yes | Yes | No |
| Secret proxy | Yes | Yes | Yes |
| Secret proxy for any API | Yes | Yes | Yes |
| Preinstalled agents | Yes | Yes | Yes |
| Agent harness API | No | No | Yes |
| MCP server | Yes | No | No |
| GPU | No | Yes | No |
| Windows | No | No | No |
| Arm64 | No | Yes | No |
| Self-hosting | No | Yes | No |
| BYOC | Yes | Yes | No |
| Open source | No | No | No |
| Scoped API keys | Yes | Not published | Yes |
| Spend limits | No | Not published | Yes |
| Usage per sandbox (API) | Yes | Yes | Yes |
| Audit logs | Not published | Yes | No |
| SSO | Yes | Yes | No |
| SOC 2 | Yes | Yes | No |
| HIPAA | Yes | Yes | No |
| EU data residency | Yes | Yes | Yes |
| Zero data retention | Yes | Not published | Yes |
Performance
On the hpc-sandbox-benchmarks Node.js build-and-test loop at 4 vCPU and 8 GB, run on September 29, 2026, bochka did 26.69 runs per second and Blaxel 19.48, so bochka got about 1.4 times the work done in the same time. Northflank Sandboxes has no result on that test, so there is no comparable CPU number for it.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Blaxel measured on: Sandbox (active time, RAM-only pricing, CPU bundled). Northflank has no published run in this suite yet, so there is no like-for-like number to compare.
Pricing in five scenarios
Each bill is priced from the providers' public price lists by the open Battleships engine, with the cheapest plan that runs the scenario.
| Scenario | Blaxel, a month | Northflank, a month | bochka, a month |
|---|---|---|---|
| One coding agent, workdays 4 vCPU / 8 GB, 50 GB disk, 8 hours a day, 22 days a month, files kept between days | $33 · Pay-as-you-go Tier 1 | $32 · Developer Sandbox (free tier) · with limits | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $120 · Pay-as-you-go Tier 1 | $108 · Developer Sandbox (free tier) · with limits | $26 · $20/mo |
| 50 agents in parallel 50 machines of 4 vCPU / 8 GB at once, 8-hour sessions, 1,100 sessions a month, Docker inside | $1,489 · Pay-as-you-go Tier 1 | $1,322 · Developer Sandbox (free tier) · with limits | $317 · $20/mo × 3 seats |
| Sandboxes for your users 2 vCPU / 4 GB, 30,000 sessions of 10 minutes a month, up to 300 at once | $396 · Pay-as-you-go Tier 2 · with limits | $361 · Developer Sandbox (free tier) · with limits | $200 · $100/mo × 2 seats |
| 1,000 short jobs at once 2 vCPU / 4 GB, 1,000 at once, 3 minutes each, 200,000 jobs a month | $876 · Pay-as-you-go Tier 2 · with limits | $688 · Developer Sandbox (free tier) · with limits | $2,000 · $2000/mo · with limits |
Blaxel: Blaxel charges for allocated RAM per second while a sandbox is active, with CPU included (8 GB comes with 4 cores). In standby you pay only snapshot storage, and volumes are billed on their full size.
Northflank: Northflank bills per second for the plan size you pick, with no monthly fee, until you pause the sandbox. Volumes cost $0.15 per GB a month even while paused, and outbound traffic costs $0.06 per GB.
Northflank: Plans start at $20 a month, and the whole fee is usage credit billed per second while a machine runs. A stopped sandbox costs nothing and keeps its whole disk.
Limits in those scenarios
Blaxel's self-serve tiers allow 10, 50 or 200 sandboxes at once, standby ones included, so 300 users or 1,000 jobs at once need a sales tier, and the lower tiers delete sandboxes after 7 or 30 days. On Northflank the limit that bites in every scenario is what survives a stop: only attached volumes keep their files, and it does not publish how many sandboxes can run at once. bochka queues starts above 90 a minute, so 1,000 short jobs at once do not all start together.
| Scenario | Blaxel | Northflank | bochka |
|---|---|---|---|
| One coding agent, workdays | None that bite |
| None that bite |
| One agent that never stops | None that bite |
| None that bite |
| 50 agents in parallel | None that bite |
| None that bite |
| Sandboxes for your users |
|
| None that bite |
| 1,000 short jobs at once |
|
|
|
Which one should you use?
Use Blaxel when
your sandboxes sit idle most of the time and must wake in milliseconds with their memory, or need tight outbound rules per domain.
- Sleeps in seconds, wakes in milliseconds. For sandboxes that sit idle most of the time: Blaxel sleeps seconds after the last connection and wakes in under 25 ms.
- Pay only while connected. For bursty agents: Blaxel bills allocated RAM per active second with CPU included, and standby costs only snapshot storage.
- Fine-grained outbound rules. For locked-down agents: Blaxel can limit a sandbox to chosen domains, down to methods and paths, with static egress IPs.
Use Northflank when
you need GPUs next to the agent, regions outside Europe and the US, or sandboxes inside your own cloud account.
- GPU sandboxes. For agents that train or run models: Northflank has GPU sandboxes from L4 and A100 up to H100 and more.
- Regions around the world. For users far from Europe and the US: Northflank also runs in Asia, Australia, South America and Africa.
- Your own cloud, one platform. For teams that must run in their own AWS, GCP or Azure account, next to their services, jobs and databases.
Where bochka fits
Blaxel is built for sandboxes that sleep most of the time, and Northflank for teams that want one platform with GPUs and many regions. If your agents instead work for hours on one machine, building, testing and running Docker or emulators, and should find it as they left it, look at bochka. It gives each agent a whole Linux VM with a real disk, a desktop, and the agent itself driven from your code.
A whole Linux machine
Blaxel's Firecracker guests get no /dev/kvm and no native SSH, and Northflank does not document /dev/kvm inside a sandbox, so Android emulators and VMs do not start. bochka gives every sandbox /dev/kvm, systemd and real SSH.
A disk that stays
Blaxel keeps files in memory, about half the RAM, unless you attach a volume at creation. A Northflank pause wipes everything outside volumes, which bill while paused. bochka saves the whole disk every minute, and stops are free.
Agents you drive from outside
Blaxel's Claude Code image and Northflank's Harnesses are reached through a terminal or SSH, so running many agents from your code means building that layer yourself. bochka lets you prompt, steer and follow seven built-in agents through one API.
Use bochka when your agents work on one machine for hours or days and should find it as they left it: installs, Docker, emulators, a desktop and a browser, with the agent driven from your code. Compare it one to one: bochka vs Blaxel and bochka vs Northflank.
Questions people ask
Is Blaxel cheaper than Northflank?
In the five scenarios we priced, Northflank's list price is a little lower, for example $108 against $120 a month for one agent that never stops. But on Northflank only attached volumes survive a stop, and Blaxel bills only while a connection is open, so an agent that disconnects often pays less on Blaxel. The same agent is $26 a month on bochka.
Which is faster, Blaxel or Northflank?
Blaxel did 19.48 runs per second on the hpc-sandbox-benchmarks Node.js test at 4 vCPU and 8 GB. Northflank has no result on that test, so we cannot compare them. bochka did 26.69 on the same test.
Can Blaxel and Northflank run Docker?
Yes. Blaxel has a Docker-in-sandbox image, and Northflank sandboxes have their own kernel, so Docker can run inside. Neither gives you /dev/kvm for Android emulators, which bochka does.
Do they keep files when a sandbox stops?
Blaxel keeps memory and processes in standby, but its files live in memory unless you attach a volume, and lower tiers delete sandboxes after 7 or 30 days. Northflank keeps only attached volumes when paused. bochka keeps the whole disk on every stop.
Does Blaxel or Northflank have GPUs?
Northflank does, with GPU sandboxes from L4 to H100 and more under gVisor. Blaxel and bochka run on CPUs only.
Where do Blaxel and Northflank run?
Blaxel runs in Oregon, North Virginia, London and Frankfurt. Northflank runs in the US, Canada, Brazil, the UK, the EU, Switzerland, Asia, Australia and South Africa, or in your own cloud. bochka runs only in the EU, in Germany, Finland and France.
Try bochka
Install the CLI, then run bochka new.
Product preview