Replit vs Instabox
Replit is an AI app builder: you describe an app, Replit Agent writes it, and Replit hosts it. Instabox, which launched today as an invite-only beta, gives each AI agent its own Linux virtual machine with root and Docker, started from a CLI, SDK or HTTP API.
The companies and products
Replit
Replit is an AI app builder and hosting platform: you describe an app in chat, Replit Agent writes it, and Replit publishes it.
You work in a browser workspace where Replit Agent sets up the project, writes the code, tests it and fixes problems, with system packages managed by Nix. When the app is ready you publish it as an Autoscale, Static, Scheduled or Reserved VM deployment, with Postgres and object storage next to it. It is built for people and teams who want a working app, not for programs that need to create many machines by API, so this page compares the parts where the two overlap.
Instabox
Instabox, made by InsForge, gives each AI agent its own Linux computer in the cloud. It launched on 2026-10-14 as an invite-only beta.
Each Instabox machine is a Firecracker microVM with its own kernel, root and Docker, started from one of four templates (agent-browser, universal, herdr or orca) or from your own snapshot. Every machine is 4 vCPU / 8 GiB with 20 GB of storage, and you drive it from a CLI, a TypeScript SDK or an HTTP API, with SSH, mosh, public port URLs and a desktop for computer use. It is aimed at developers who want a cloud box for a coding agent.
- Isolation
- Firecracker microVM per machine
- Machines per account
- 5, in any state: paused and stopped ones count
- Company
- InsForge AI, Inc.
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. “181st cheapest of 367” means 180 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 | Replit: price rank | Instabox: price rank | boat: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month A software factory starts many agents from code: Replit's outside entry point is an MCP server that drives Replit Agent one app at a time, and Instabox stops at 5 machines per account. | 181st of 367, with limits $2,000 a month | No published price | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB An always-on assistant on Replit is a Reserved VM that runs and bills all month; Instabox can keep a machine on, but it pauses after 30 idle minutes unless you turn that off. | 202nd of 366, with limits $2,033 a month | No published price | 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 Replit's Autoscale bills only while it serves requests, so short runs cost little there, though it is a web host, not a code runner; Instabox API exec calls run at most 10 minutes, 4 at once. | 228th of 345, with limits $146 a month | No published price | 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 Neither fits one sandbox per user today: Replit does not publish how many deployments can run at once, and Instabox allows 5 machines per account, stopped ones included. | 233rd of 361, with limits $825 a month | No published price | 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 | 258th of 360, with limits $4,226 a month | No published price | 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 Instabox's 5-machine cap limits how many evals run at once, and Replit has no API to start a machine per eval. | 265th of 364, with limits $685 a month | No published price | 10th cheapest of 364 $200 a month |
| CI runners 40 at once · 8 vCPU / 16 GB · 6,000 sessions of 12 min a month CI jobs that build containers need Docker, which Instabox runs and Replit's Nix-based environments do not document; jobs that need /dev/kvm have it on boat only. | 275th of 377, with limits $425 a month | No published price | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB Both work for coding in the cloud: Replit has a browser workspace with SSH on paid plans, and Instabox has SSH through a gateway with mosh. | 165th of 368, with limits $109 a month | No published price | 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 Replit's VNC pane shows a desktop to a person, with no API for an agent; Instabox has a desktop template with a screenshot and click API, and boat streams a desktop at 60fps. | 190th of 369, with limits $619 a month | No published price | 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 | 229th of 367, with limits $317 a month | No published price | 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 | 234th of 346, with limits $217 a month | No published price | 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 | 150th of 338, with limits $4,378 a month | No published price | 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 | 208th of 360, with limits $215 a month | No published price | 2nd cheapest of 360 $200 a month |
| GPU eval jobs 10 at once · 8 vCPU / 32 GB · 500 sessions of 30 min a month | Can't run it | No published price | 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 | No published price | Can't run it |
Key features
| Feature | Replit | Instabox | boat |
|---|---|---|---|
| Kind of product | AI app builder with browser workspaces and app hosting | A Linux VM per agent, in an invite-only beta | Sandboxes you create, stop and fork by API, SDK or CLI |
| Isolation | Not documented; the security page says strong logical separation between users | Firecracker microVM with its own kernel and root | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| Creating machines from code | MCP server tools to create, update and publish apps; no API to start many machines | CLI, TypeScript SDK and HTTP API, up to 5 machines per account | API, SDK and CLI to create, stop, resume and fork many sandboxes |
| Machine sizes | Reserved VM sizes at a fixed monthly price each, such as 4 vCPU / 16 GB | One size for everyone: 4 vCPU / 8 GiB with 20 GB storage | Several sizes, up to 8 vCPU / 16 GB on the $20 plan and 16 vCPU / 32 GB on $100 and above |
| Docker | System packages come from Nix; the docs do not describe Docker or systemd | Docker and Docker Compose run inside, with root | Docker and Compose run inside, with root and systemd |
| Nested virtualization | Not documented | Not documented | Yes, /dev/kvm for Android emulators and VMs |
| Fork and snapshots | Workspace files and Agent checkpoints at milestones | Fork copies a stopped machine; snapshots are saved by hand, up to 10 | Fork a running sandbox; disk saved every minute and on stop |
| Pause and resume | Reserved VM runs continuously; Autoscale goes idle after 15 minutes | Pause keeps memory and running programs; resume usually takes about a second | Stop keeps the disk and costs nothing; start boots the machine again |
| Hosting that wakes on a request | Autoscale starts on the first request and costs nothing while idle | Port URLs go offline while a machine is paused, and a visit does not wake it | No wake on request; you stop and resume sandboxes yourself |
| Reaching the machine | Published apps on HTTPS domains, custom domains and private deployments; SSH into the workspace on paid plans | HTTPS on up to 16 ports, open to anyone with the URL; SSH gateway with mosh and paste-anywhere SSH tokens | HTTPS on up to 50 ports, token-protected by default; raw TCP; SSH |
| Desktop and computer use | VNC pane that streams a desktop to your browser; no computer-use API | Linux desktop with a browser on one template, screenshot and click API; you bring the model | 60fps Linux desktop with Chromium and a computer-use agent |
| Coding agents | Replit Agent, which you can also drive from an MCP client | Templates and saved agent sign-ins in snapshots; you run the agent yourself | Seven agents preinstalled, with a prompt, steer and events API |
| Keeping API keys out of the machine | Replit manages keys for OpenAI, Anthropic, Google and OpenRouter models; other keys are secrets in the app | Vault writes your secrets into each machine as environment variables or files | Credentials proxy: real keys never enter the sandbox, for model providers and any HTTPS API |
| Regions | North America, Europe, Asia, South America and Australia for published apps on Core and up | Not published | EU only (Germany, Finland, France) |
Every feature Battleships tracks (43)
| Feature | Replit | Instabox | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | No | Yes | Yes |
| Nested virtualization | No | Not published | Yes |
| Root | Not published | Yes | Yes |
| Systemd | No | Not published | Yes |
| Desktop GUI | Yes | Yes | Yes |
| Browser | No | Yes | Yes |
| Computer-use API | No | Yes | Yes |
| SSH | Yes | Yes | Yes |
| Persistent disk | Yes | Yes | Yes |
| Pause/resume | No | Yes | Yes |
| Automatic snapshots | Yes | No | Yes |
| Fork/clone | Yes | Yes | Yes |
| Live fork (no pause) | No | No | Yes |
| Memory fork | No | No | No |
| Custom image (Docker or snapshot) | Yes | Yes | Yes |
| ≥24 h sessions | Yes | Yes | Yes |
| Idle auto-stop | Yes | Yes | No |
| Wake on request | Yes | No | No |
| HTTPS preview URLs | Yes | Yes | Yes |
| Raw TCP inbound | Not published | Not published | Yes |
| Public IPv4 | No | No | No |
| Egress allowlist | No | Not published | No |
| Secret proxy | Yes | No | Yes |
| Secret proxy for any API | No | No | Yes |
| Preinstalled agents | Yes | Not published | Yes |
| Agent harness API | Yes | Not published | Yes |
| MCP server | Yes | Not published | No |
| GPU | No | No | No |
| Windows | No | No | No |
| Arm64 | Not published | Not published | No |
| Self-hosting | No | Not published | No |
| BYOC | No | Not published | No |
| Open source | No | No | No |
| Scoped API keys | Not published | Yes | Yes |
| Spend limits | Yes | Not published | Yes |
| Usage per sandbox (API) | Yes | Yes | Yes |
| Audit logs | Yes | Not published | No |
| SSO | Yes | No | No |
| SOC 2 | Yes | Not published | No |
| HIPAA | No | Not published | No |
| EU data residency | Yes | Not published | Yes |
| Zero data retention | Not published | Not published | Yes |
Performance
There is no comparable measurement for Replit or Instabox: neither is in StarSling's public benchmark, so this page makes no speed claim between them. boat did 26.69 Node.js build-and-test runs per second at 4 vCPU / 8 GB. Instabox says a new machine's shell is ready in under a second; that has not been measured.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Replit and Instabox have 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 | Replit, a month | Instabox, a month | boat, 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 | $122 · Pro $100 (annual) · with limits | No published price | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $122 · Pro $100 (annual) · with limits | No published price | $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 | $1,330 · Pro $1,000 (annual) · with limits | No published price | $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 | $403 · Pro $250 (annual) · with limits | No published price | $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 | $825 · Pro $1,000 (annual) · with limits | No published price | $2,000 · $2000/mo · with limits |
Replit: Replit plans (Core $20, Pro from $100) turn into monthly credits for Agent work and hosting, then usage goes on to pay-as-you-go. A Reserved VM has a fixed monthly price per size, such as $130 for 4 vCPU / 16 GB, and bills whether busy or idle.
Instabox: Instabox is free during the beta, with 5 machines per user, and publishes no price yet ("Free until we figure it out"), so no bill can be compared.
Instabox: Plans start at $20 a month, and the whole fee is usage credit spent per second while a sandbox runs. A stopped sandbox costs nothing and keeps its disk.
Limits in those scenarios
Replit is marked as not a fit in every scenario because it is an app platform: one Reserved VM is one published app that runs all month, and it does not publish how many can run at once. Instabox cannot be priced in any scenario because it has no published rate, and its limits bite too: 5 machines per account rules out 50 agents or 300 user sandboxes, and 20 GB of storage is less than the 50 GB disk the agent scenarios ask for. On boat, the 1,000-job burst is queued above 90 starts a minute and needs more starts per day than the $2,000 plan allows.
| Scenario | Replit | Instabox | boat |
|---|---|---|---|
| One coding agent, workdays |
|
| None that bite |
| One agent that never stops |
|
| None that bite |
| 50 agents in parallel |
|
| None that bite |
| Sandboxes for your users |
|
| None that bite |
| 1,000 short jobs at once |
|
|
|
Which one should you use?
Use Replit when
you want Replit Agent to build a web app from a description and host it for you, with databases, sleeping when idle, or regions outside Europe.
- An app built and hosted for you. Useful if you want a working app from a description: Replit Agent builds, tests and publishes it, with Postgres and storage.
- Hosting that costs nothing when idle. Useful for web apps with uneven traffic: Autoscale wakes on the first request and costs nothing while idle.
- Regions on five continents. Useful if your users are spread out: published apps can run in North America, Europe, Asia, South America or Australia.
Use Instabox when
you want to try a few free 4 vCPU / 8 GiB agent machines with Docker during its invite-only beta, with memory pause and mosh.
- A real VM with Docker. Useful for agents that run containers: each machine is a Firecracker microVM with its own kernel, root and Docker.
- Pause with memory. A paused machine keeps its memory and running programs and usually resumes in about a second.
- SSH gateway with mosh. Its SSH gateway relays mosh and gives paste-anywhere SSH tokens, so a session survives sleep and network changes.
Where boat fits
If what you are really running is agents started by your own code, Replit is the wrong shape and Instabox is still small: one size, 5 machines and no published terms. boat gives each agent a full VM by API, with Docker, /dev/kvm, live forks, private URLs and keys kept outside, at published prices today.
Many machines, started by code
Replit has no API to start many machines, so each always-on agent is a published Reserved VM app. Instabox has an API but stops at 5 machines of 4 vCPU / 8 GiB, stopped ones included. boat has no session cap on paid plans and sizes up to 16 vCPU / 32 GB.
Docker, KVM and forks of running work
Replit does not document Docker or systemd, so jobs must fit into Nix packages. Instabox runs Docker but does not document /dev/kvm, and its fork needs a stopped machine, which ends running programs. boat forks a running sandbox and has /dev/kvm.
Keys and URLs agents cannot leak
On Replit, keys other than AI models sit in the app as secrets, and Instabox writes secrets into the machine and serves port URLs anyone can open. boat's credentials proxy keeps real keys outside, and its port URLs carry a token by default.
Use boat when your own code starts agents: full VMs with Docker and /dev/kvm, forks of running work, private port URLs, bigger sizes, more than five at once, and published terms. Compare it one to one: boat vs Replit and boat vs Instabox.
Questions people ask
Is Replit cheaper than Instabox?
It can't be compared yet. Instabox is free during the beta, with 5 machines per user, and publishes no price, so there is no bill to set against Replit's. For one coding agent on workdays we price Replit at $122 a month and boat at $20 a month.
Which is faster, Replit or Instabox?
Neither has been benchmarked, so we can't say. Instabox says a new machine's shell is ready in under a second, and its docs say a paused machine usually resumes in about a second; neither has been measured here. boat did 26.69 runs per second in StarSling's public benchmark.
Can Replit or Instabox run Docker?
Instabox runs Docker and Docker Compose inside each machine. Replit sets up environments with Nix packages and does not describe running Docker. Every boat sandbox has Docker, root, systemd and /dev/kvm.
Can I start many machines from code?
Not many on either. Replit's MCP server drives Replit Agent one app at a time, with no API to start machines. Instabox has an API but allows 5 machines per account, paused and stopped ones included. boat starts and forks many sandboxes by API.
Can anyone use Instabox?
Not yet. It launched on 2026-10-14 as an invite-only beta, with sign-in through GitHub or Google. Its regions, terms and later price are not published.
Is boat SOC 2 compliant?
SOC 2 is in progress. We're open about where we stand: live status at status.ascii.dev and our data retention policy at docs.boat.dev/data-retention. Replit's docs say it has a SOC 2 Type 2 attestation, and Instabox publishes no compliance information.
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