Cloud Computers for AI Agents in 2026: A Practical Comparison

Overview

An AI agent that only talks is cheap to host. The moment it needs to install packages, run tests, start a server, or leave a job running overnight, it needs a computer of its own. Handing it yours means giving a language model a shell on the machine that holds your SSH keys. A whole category of products now rents that computer by the second. They look alike on their landing pages, but underneath they make very different choices.

Comparison Table

Product	Isolation	Max Lifetime	Keeps Memory on Pause	GPU Support	2 vCPU / 4 GB Price (1 hr)
machine0	Full KVM VM	Indefinite	No (disk snapshot)	Yes (up to 8x H200)	$0.052
OpenComputer (v2)	Full KVM VM	8 hours	No	Yes	$0.378
E2B	Firecracker microVM	1 hour (hobby) / 24 hours (pro)	Yes, kept indefinitely	N/A	$0.166
Daytona	Container (VM optional)	Up to 8 hours	No (auto-stops after 15 min idle)	Yes (up to 8 GPUs)	$0.166
Fly.io Sprites	Firecracker microVM	None (sleeps when idle)	No (loses memory on wake)	N/A	$0.315 (usage-billed)

All prices are based on 2 vCPU / 4 GB running at full CPU for one hour, as of September 26, 2026.

machine0

machine0 is a real VM your agent keeps. Launched on Hacker News on August 18, 2026 as a YC Summer 2026 company, it is the most traditional product here. The founder's launch post states: "Every machine is a full KVM virtual machine, not a container or sandbox." Its VMs run on DigitalOcean infrastructure across five regions. You get a dedicated public IP (kept across stop, replaced on suspend), SSH as user ubuntu with password login disabled, and an authenticated HTTPS URL at https://<name>.mac0.io that proxies to port 80. There is no language SDK. The interface is a CLI (list and detail commands take --json) plus a remote MCP server.

Example Usage

npm install -g @machine0/cli # or: curl -LsSf https://machine0.io/install.sh | sh
machine0 new agent-box --size large --region eu --image ubuntu-24-04-loaded
machine0 ssh agent-box "git clone https://github.com/your-org/app.git && cd app && npm ci && npm test"
machine0 suspend agent-box # snapshot the disk, delete the instance, stop compute billing
machine0 start agent-box # restore later, with a new IP

The loaded image ships Docker, Node.js, Python, Go, Rust, Bun, Claude Code, Codex, and OpenCode. To give Claude Code control of your fleet, run claude mcp add --transport http machine0 https://app.machine0.io/mcp.

Tradeoffs: Provisioning takes one to three minutes (not milliseconds). Stopped VMs are still billed at full rate, so you must suspend to save money. Suspending keeps the disk but not running processes. Sizes range from small (1 vCPU, 1 GB, $0.013/hour) to 6xl (60 vCPU, 240 GB). GPU sizes go up to 8x H200 at $39.336/hour, billed per minute.

OpenComputer

OpenComputer comes from the team behind Digger and is open source under Apache-2.0 (554 stars). Its docs describe a sandbox as "Not a container. Real VM with its own kernel, memory, and disk," and the self-hosting guide describes a control plane driving QEMU/KVM on KVM-capable Linux workers. The v1 runtime is retired, and a 0.x SDK now provides 410 GB.

On v2, the lifetime page is blunt: "The ceiling is 8 hours, and it counts running and hibernated time together. It cannot be extended." Checkpoints no longer capture memory, forking from a checkpoint is not available yet, RAM comes in fixed steps of 1, 2, 4, or 8 GB, and disk is fixed at about 16 GB.

Example:

import { Sandbox } from "@opencomputer/sdk";

const sandbox = await Sandbox.create();
const result = await sandbox.exec.run("echo Hello from $(uname -a)");
console.log(result.stdout);
await sandbox.kill();
sandbox.getPreviewDomain(3000).then(url => {
  // public URL for the dev server
});

Pricing is per second: $0.0063 per minute for 4 GB and 2 vCPU, with $10 of free credit. Use it for bounded jobs that finish inside a working day.

E2B

E2B is the sandbox most agent frameworks reach for first. Its SDK repo has 14,008 stars and its backend (e2b-dev/runtime) is Apache-2.0 and self-hostable. Because a new sandbox is a snapshot restore, the docs put startup at about 150 ms. The feature that sets it apart is pause: the persistence docs say pausing saves "not only state of the sandbox's filesystem but also the sandbox's memory," that a paused sandbox "is kept indefinitely," and that resume takes about a second (pausing takes about 4 seconds per GiB of RAM).

Example:

from e2b import Sandbox

sandbox = Sandbox.create(timeout=600, lifecycle={"on_timeout": "pause"})
result = sandbox.commands.run(
    "git clone https://github.com/your-org/app.git app && cd app && npm ci && npm test"
)
print(result.stdout)
print(sandbox.get_host(3000))
sandbox.pause()
sandbox.connect(sandbox_id)

Limits: the default sandbox is 2 vCPU and 512 MiB of RAM, and you change that by building a template. The FAQ is explicit that sandboxes are "CPU-only." SSH requires a custom template with a WebSocket proxy. Hobby is free with $100 of one-time credit; Pro is $150/month.

Daytona

Daytona charges exactly E2B's per-second rates ($0.0504 per vCPU-hour, $0.0162 per GiB-hour) and adds $200 of free compute. It covers more ground: GPU sandboxes up to 8 GPUs, Windows VMs, built-in SSH (daytona ssh), an MCP server in the CLI, and SDKs for Python, TypeScript, Ruby, Go, and Java. The catch is near the top of its sandbox docs: "Sandboxes run as Linux containers by default." Memory-preserving pause and fork only work on VM sandboxes. The default auto-stop is 15 minutes, and the docs warn that "Merely having a script or background task running is not sufficient to keep the sandbox alive," so a long npm test with no API calls can be stopped mid-run unless you set auto_stop_interval=0. Also note that the 71,697-star daytonaio/daytona repo stopped receiving updates in June 2026, when core development moved to a private codebase.

from daytona import Daytona, DaytonaConfig

daytona = Daytona(DaytonaConfig(api_key="YOUR_API_KEY"))
sandbox = daytona.create()
response = sandbox.process.exec("echo 'Hello from Daytona'")
print(response.result)

Fly.io Sprites

Sprites sit between machine0 and a sandbox. Each one is a Firecracker microVM with 8 vCPUs, 100 GB of storage on Ubuntu 25.10, and its own HTTPS URL. When idle it sleeps, and the next command or HTTP request wakes it: about 100 to 500 ms from a warm suspend with processes intact, or 1 to 2 seconds from cold, which keeps the disk but loses memory.

Example:

curl -fsSL https://sprites.dev/install.sh | sh
sprite create agent-box
sprite exec -- echo "Hello, Sprites!"
sprite checkpoint create --comment "tests passing"

Checkpoints are copy-on-write disk snapshots. The URL routes to port 8080, not 3000, and needs a token unless you run sprite config update --url-auth public.

Vercel Sandbox

Vercel Sandbox says "each sandbox runs in its own Firecracker microVM with a dedicated kernel," snapshots the filesystem when a sandbox stops, and bills only active CPU: "Time spent waiting for I/O (such as network requests, database queries, or AI model calls) does not count." That matters for agents, which spend most of their time waiting on a model. Hobby is free with 5 CPU-hours a month and 45-minute sessions. The SDK is @vercel/sandbox (3.5.0), and it authenticates through a Vercel project's OIDC token, fitting best if you already deploy there.

Modal

Modal Sandboxes use gVisor, with full-VM sandboxes in beta. They bring GPUs from T4 to B300 and scale to very large numbers of concurrent sandboxes, but the maximum lifetime is 24 hours and there is no pause, only filesystem snapshots (memory snapshots are alpha and expire after 7 days). If your agent needs a desktop, computer-use agents that click through a GUI need a screen, not just a shell.

Honorable Mentions

These five are newer or a slightly different shape. I read their docs and pricing pages on September 29, 2026, but did not run them.

• Boat (YC Fall 2026): Rents full Ubuntu VMs with /dev/kvm passed through, at the lowest price in this post: $0.018/hour for 2 vCPU / 4 GB, billed per second on top of a $20/month plan. Catch: vCPUs are shared, hosted in the EU only, and snapshots keep the filesystem but not memory.

• Freestyle (YC S24): Runs full VMs on its own bare-metal racks that pause with memory intact, and new VMs can start from memory-and-disk snapshots. 2 vCPU / 4 GiB is about $0.13/hour, with the monthly allowance covering roughly the first 100 hours. The SDK is TypeScript only, and its own docs say it oversubscribes hosts, so skip it for production-critical workloads.

Summary

For a coding agent that works on one repo for a week, the persistent computer camp (machine0, Fly.io Sprites) is the right choice. For a product that runs untrusted code for thousands of users who need ephemeral isolation, the sandbox camp (OpenComputer, E2B, Daytona, Vercel, Modal) is better suited. The key decision points are whether you need persistence (machine0, Sprites) versus speed and isolation (E2B, OpenComputer, etc.), and whether your budget prioritizes low base cost (Boat) over features (Freestyle).