Replit vs Azure Container Apps Sandboxes
Replit is an AI app builder: you describe an app, Replit Agent writes it, and Replit hosts it. Azure Container Apps Sandboxes is a service inside Azure where your code creates isolated microVMs by SDK that suspend with their memory and wake on traffic.
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.
Azure Container Apps Sandboxes
Azure Container Apps Sandboxes is a service inside Microsoft Azure that gives each agent or user an isolated microVM you create, suspend and resume through an SDK.
It is part of Azure Container Apps, the hyperscaler's serverless container platform, and lives in your Azure subscription as a sandbox group resource. Each sandbox boots from an OCI image or a snapshot, has its own kernel, and can be suspended with its memory and resumed in under a second. It is built for teams already on Azure that want stateful code execution with Azure networking, identity and billing.
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 | Azure Container Apps Sandboxes: 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; Azure can create sandboxes by SDK, Replit drives one app at a time through Replit Agent, and boat adds SSH, /dev/kvm and agents you steer by API. | 181st of 367, with limits $2,000 a month | 288th of 367, with limits $5,276 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB An always-on assistant is a Reserved VM app on Replit and a running sandbox billed every second on Azure; boat keeps one on for weeks with a desktop and SSH. | 202nd of 366, with limits $2,033 a month | 302nd of 366, with limits $6,544 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 Azure fits short code runs well: a sandbox suspends with its memory and resumes in under a second, while Replit is a web host, not a code runner. | 228th of 345, with limits $146 a month | 34th cheapest of 345 $354 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 Azure fits sandboxes for your users, with idle ones suspended; Replit does not publish how many deployments can run at once, and boat gives each user a full VM with hosting on up to 50 ports. | 233rd of 361, with limits $825 a month | 22nd cheapest of 361 $2,260 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 | 258th of 360, with limits $4,226 a month | 153rd of 360, with limits $10,740 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 | 265th of 364, with limits $685 a month | 75th cheapest of 364 $1,728 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 CI that builds containers needs Docker, which Azure has in some images and Replit does not document; boat also has /dev/kvm for Android and VM builds. | 275th of 377, with limits $425 a month | 103rd cheapest of 377 $1,046 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB A dev box wants SSH; Replit gives SSH into the workspace on paid plans, Azure gives a shell only through its CLI or portal, and boat gives SSH and raw TCP. | 165th of 368, with limits $109 a month | 322nd of 368, with limits $262 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 Computer-use agents need a screen; Replit's VNC pane is for a person, Azure's sandboxes are headless, and boat streams a desktop at 60fps. | 190th of 369, with limits $619 a month | 279th of 369, with limits $1,573 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 Neither Replit nor Azure ships a managed browser; boat has Chromium on a desktop in every sandbox. | 229th of 367, with limits $317 a month | 288th of 367, with limits $795 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 | 234th of 346, with limits $217 a month | 284th of 346, with limits $561 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 | 150th of 338, with limits $4,378 a month | 239th of 338, with limits $10,956 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 | 208th of 360, with limits $215 a month | 278th of 360, with limits $517 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 | Can't run it | Can't run it | 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 | Replit | Azure Container Apps Sandboxes | boat |
|---|---|---|---|
| Kind of product | AI app builder with browser workspaces and app hosting | Sandboxes you create, suspend and resume by SDK inside Azure Container Apps | Sandboxes you create, stop and fork by API, SDK or CLI |
| Isolation | Not documented; the security page says strong logical separation between users | MicroVM per sandbox with its own kernel | 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 | SDK and CLI to create sandboxes from an OCI image or a snapshot | API, SDK and CLI to create, stop, resume and fork many sandboxes |
| Docker and systemd | System packages come from Nix; Docker and systemd are not documented | Depends on the image: azure-dev ships Docker on systemd; the default ubuntu image has only Buildah | Docker, systemd and root on every sandbox |
| Nested virtualization | Not documented | Not documented | Yes, /dev/kvm for Android emulators and VMs |
| Getting a shell | SSH into the workspace on paid plans | Interactive shell through the aca CLI, SDK or portal; no SSH | SSH, plus CLI and API exec |
| Suspend and resume | Autoscale apps go idle after 15 minutes and wake on the next request | Suspend with memory and disk; resume in under a second with processes running | Disk saved every minute and on stop; a stopped sandbox costs nothing; resume boots the machine again |
| Fork | Agent checkpoints at milestones you can roll back to | Snapshot a running sandbox with its memory and create new sandboxes from it | Fork a running sandbox with its disk |
| Desktop and computer use | VNC pane that streams a native desktop to your browser; no computer-use API | Headless; no desktop or managed browser | Linux desktop streamed at 60fps, Chromium and computer-use tools preinstalled |
| Coding agents | Replit Agent, which you can also drive from an MCP client | Copilot CLI and Claude Code images, run through the exec API | Claude Code, Codex, OpenCode and more preinstalled, with a prompt, steer and events API |
| Keeping keys out of the sandbox | Replit manages keys for some AI model providers; other keys are secrets in the app | Group secrets usable in egress header rules; Copilot and Anthropic tokens are injected into the sandbox at startup | Credentials proxy for model providers and any HTTPS API; switch a credential to another account when credits run out |
| Reaching the machine | Published apps on HTTPS domains, custom domains and private deployments | Public HTTPS routes per published port; private endpoint from your VNet at extra cost; no public IP | HTTPS URLs for up to 50 ports, token-protected; raw TCP; dedicated IPv4 or IPv6 |
| Outbound rules | Open internet; no egress rules | Egress policy with allow, deny, rewrite and header rules by host, path and method; VNet integration | Open internet, no provider-side allowlist |
| Databases and hosting | Postgres and App Storage built into each app; Autoscale costs nothing while idle | No hosted app platform in the sandbox service itself | No hosted databases; run your own inside a sandbox |
Every feature Battleships tracks (43)
| Feature | Replit | Azure Container Apps Sandboxes | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | No | Yes | Yes |
| Nested virtualization | No | No | Yes |
| Root | Not published | Yes | Yes |
| Systemd | No | Yes | Yes |
| Desktop GUI | Yes | No | Yes |
| Browser | No | No | Yes |
| Computer-use API | No | No | Yes |
| SSH | Yes | No | Yes |
| Persistent disk | Yes | Yes | Yes |
| Pause/resume | No | Yes | Yes |
| Automatic snapshots | Yes | Yes | Yes |
| Fork/clone | Yes | Yes | Yes |
| Live fork (no pause) | No | Yes | Yes |
| Memory fork | No | Yes | 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 | Yes | No |
| HTTPS preview URLs | Yes | Yes | Yes |
| Raw TCP inbound | Not published | No | Yes |
| Public IPv4 | No | No | No |
| Egress allowlist | No | Yes | No |
| Secret proxy | Yes | Yes | Yes |
| Secret proxy for any API | No | Yes | Yes |
| Preinstalled agents | Yes | Yes | Yes |
| Agent harness API | Yes | No | Yes |
| MCP server | Yes | No | No |
| GPU | No | No | No |
| Windows | No | No | No |
| Arm64 | Not published | No | No |
| Self-hosting | No | No | No |
| BYOC | No | No | No |
| Open source | No | No | No |
| Scoped API keys | Not published | Not published | Yes |
| Spend limits | Yes | Yes | Yes |
| Usage per sandbox (API) | Yes | Yes | Yes |
| Audit logs | Yes | Yes | No |
| SSO | Yes | Yes | No |
| SOC 2 | Yes | Yes | No |
| HIPAA | No | Yes | No |
| EU data residency | Yes | Yes | Yes |
| Zero data retention | Not published | Not published | Yes |
Performance
There is no comparable measurement for Replit or Azure Container Apps Sandboxes. boat did 26.69 Node.js build-and-test runs per second at 4 vCPU / 8 GB in StarSling's public benchmark, on dedicated AMD Ryzen 9 9950X hosts. Until the other two are measured on the same test, this page makes no speed claim.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Replit and Azure Container Apps Sandboxes 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 | Azure Container Apps Sandboxes, 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 | $68 · Pay-as-you-go | $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 | $262 · Pay-as-you-go · 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 | $1,330 · Pro $1,000 (annual) · with limits | $3,421 · Pay-as-you-go | $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 | $989 · Pay-as-you-go | $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 | $2,148 · Pay-as-you-go | $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 to pay-as-you-go. A Reserved VM has a fixed monthly price per size and bills whether busy or idle; Autoscale bills only while it serves requests.
Azure Container Apps Sandboxes: Azure bills per second on the Container Apps Consumption meters for the vCPU and memory of the sandbox's tier while it runs, idle time before auto-suspend included. There is no plan fee, and some regions charge more per second.
Azure Container Apps Sandboxes: Plans start at $20 a month, and the whole fee is usage credit spent per second on running sandboxes. 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: each always-on machine is a published Reserved VM app, it does not document Docker, and it does not publish how many deployments can run at once. Azure fits most scenarios but bills a running sandbox every second until it suspends, so the always-on agent only fits with a 3-year commitment, and its default quota of 500 active cores caps a fleet until support raises it. boat fits every scenario except 1,000 short jobs at once, where the $2,000 plan queues starts above 90 a minute.
| Scenario | Replit | Azure Container Apps Sandboxes | boat |
|---|---|---|---|
| One coding agent, workdays |
| None that bite | None that bite |
| One agent that never stops |
|
| None that bite |
| 50 agents in parallel |
| None that bite | None that bite |
| Sandboxes for your users |
| None that bite | None that bite |
| 1,000 short jobs at once |
| None that bite |
|
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 and hosting that sleeps when idle.
- 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.
- No cloud account to set up. Useful for people who just want to code in a browser, with no Azure subscription, Entra ID or roles to configure.
Use Azure Container Apps Sandboxes when
your team already runs on Azure and your code needs short stateful sandboxes that suspend with their memory, wake on traffic or sit behind strict egress rules.
- Sandboxes your code creates. Useful if your program needs one isolated microVM per task or user, created and suspended through an SDK.
- Memory suspend and wake on traffic. Good for stateful jobs that sleep between requests: a sandbox suspends with its memory and resumes in under a second.
- Fine-grained outbound rules inside Azure. Teams on Azure get egress rules by host, path and method, VNets and Entra ID, in 40 regions.
Where boat fits
If what you are really running is agents that do real work, look at boat. Replit is built to host apps a person makes, and Azure is built for short headless code runs inside an Azure account. boat gives each agent a whole computer with SSH, Docker, /dev/kvm, a desktop and coding agents you drive from outside.
A whole computer with Docker and KVM
An agent that runs docker compose or boots an Android emulator stalls on Replit, which documents only Nix packages, and on Azure, which needs a Docker image like azure-dev and documents no nested virtualization.
A screen and a browser for every agent
Replit's VNC pane is for a person and Azure's sandboxes are headless, so a computer-use agent on either needs its own browser, display and streaming stack. boat streams a 60fps desktop with Chromium in every sandbox.
Agents driven from outside, keys kept outside
Replit's MCP server drives only Replit Agent, and Azure runs agents through raw exec with tokens injected into the sandbox. boat lets you prompt, steer and stream agents by API, while its proxy keeps real keys outside.
Use boat when your agents need a whole computer for real work: SSH, Docker, emulators, a desktop and a browser, with coding agents and a credentials proxy built in. Compare it one to one: boat vs Replit and boat vs Azure Container Apps Sandboxes.
Questions people ask
Is Replit cheaper than Azure Container Apps Sandboxes?
In our scenarios Replit's bill is lower, for example $1,330 against $3,421 for 50 agents in parallel, but Replit does not fit any of them as a sandbox. Among the ones that fit, boat comes to $317 for that fleet and $20 for one agent on workdays, against $68 on Azure.
Which is faster, Replit or Azure Container Apps Sandboxes?
Neither has a comparable CPU measurement, so we cannot say. boat did 26.69 runs per second on StarSling's Node.js benchmark at 4 vCPU / 8 GB.
Can Replit or Azure Container Apps Sandboxes run Docker?
Replit's docs set up environments with Nix packages and do not describe Docker. On Azure, the azure-dev image ships Docker on systemd, while the default ubuntu image has only Buildah. Every boat sandbox has Docker, systemd and /dev/kvm.
Is Replit a sandbox for AI agents?
Not in the usual sense. Replit is an app builder where Replit Agent writes and publishes apps, with no API to start many machines. Azure Container Apps Sandboxes and boat are both sandboxes your code creates.
Can I SSH into them?
Replit offers SSH into the workspace on paid plans. Azure gives an interactive shell through the aca CLI, SDK or portal, with no SSH. Every boat sandbox has SSH and raw TCP.
Where do they run?
Replit hosts data mainly on Google Cloud in the United States and publishes apps on five continents on Core and up. Azure runs in 40 regions, 9 of them in the EU. boat runs only in the EU, in Germany, Finland and France.
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