# Sandboxes FAQ

> Short answers about Sandboxes (beta): speed, forking, isolation, pricing, limits, what is not there yet, and where to get help.

URL: https://prized.dev/docs/sandboxes-faq

New here? [Open Sandboxes](https://prized.dev/onboarding/sandboxes) to sign up and make an API key, then run the [Quickstart](https://prized.dev/docs/sandboxes#quickstart).

## Basics [#basics]

### What is a sandbox? [#what-is-a-sandbox]

Sandboxes (beta) are Linux microVMs that your code creates, runs commands in, pauses, forks, and deletes through the [API](https://prized.dev/docs/sandboxes-api) or the [CLI](https://prized.dev/docs/cli#sandboxes). Unlike a [box](https://prized.dev/docs/sandboxes#sandboxes-and-boxes), the machine you work on every day, a sandbox is for one job at a time and lives 24 hours at most.

### How fast is it? [#how-fast-is-it]

A create is usually running in 4 to 5 seconds, a resume in about two, and a fork's copies within a few seconds. At busy moments a create can wait in `starting` while capacity is added, or answer `503 sandbox_capacity` with `Retry-After` and bill nothing ([Limits: Sandboxes](https://prized.dev/docs/limits#sandboxes)).

### What is inside one? [#what-is-inside-one]

Ubuntu 24.04 with Python 3, Node.js 22, git, and build tools (`prized-base-v1`), or all of that plus Claude Code and Codex (`prized-agent-v1`). Each takes 1 to 8 vCPU, 1 to 16 GB of memory, and 10 to 100 GB of disk ([Templates](https://prized.dev/docs/sandboxes#templates)).

### Where do sandboxes run? [#where-do-sandboxes-run]

In `us-west-2` (Oregon). Other regions are not available yet.

## Forking [#forking]

### What does a fork copy? [#what-does-a-fork-copy]

Each copy starts with the parent's memory, disk, and running processes as they were at the fork, and the parent keeps running after a brief pause, usually under a second. Copies are ordinary sandboxes, billed and counted against your quotas like any other ([Fork](https://prized.dev/docs/sandboxes#fork)).

### How many copies can one fork make? [#how-many-copies-can-one-fork-make]

As many as fit on the parent's machine and in your workspace's [quotas](https://prized.dev/docs/limits#sandboxes): at most 31 copies of a 1 vCPU sandbox, 15 of a 2 vCPU one, 7 of a 4 vCPU one, and 3 of an 8 vCPU one; more memory or disk, or a busy machine, fits fewer. A fork that does not fit makes nothing and answers `409 fork_capacity` with `fits`, how many fit now: fork that many, or start a new sandbox and fork that.

### Do copies share randomness or identity? [#do-copies-share-randomness-or-identity]

Each copy gets its own hostname, IP address, and `/etc/machine-id`, and a freshly reseeded kernel random number generator; its connections to other machines are closed, and loopback ones keep working. Process IDs and `boot_id` stay the parent's, and a process that was already running keeps the random state it holds in memory, so reseed or restart it after a fork before it makes keys, tokens, or IDs.

## Security and isolation [#security-and-isolation]

### How are sandboxes isolated, and what can they reach? [#how-are-sandboxes-isolated-and-what-can-they-reach]

Each sandbox is its own microVM with its own kernel. It reaches the internet outbound, nothing reaches it from the internet, and sandboxes cannot reach each other ([Security and trust](https://prized.dev/docs/security#on-the-box)).

### Do I get root? [#do-i-get-root]

No: commands run as the user `prized`, without sudo, so there is no `apt`. `pip` installs into a venv, and `npm install -g` needs a user prefix ([Inside a sandbox](https://prized.dev/docs/sandboxes#inside-a-sandbox)).

### What can Prized see? [#what-can-prized-see]

Commands and files pass through Prized's edge, which checks your API key on every request; the key never enters the sandbox, and the [`envVars`](https://prized.dev/docs/sandboxes#environment-variables) you set are stored encrypted and never returned by any route. A running sandbox reports resource vitals, listening ports, and its top processes, never file names, file contents, or terminal output ([Security and trust](https://prized.dev/docs/security#data-at-rest-and-in-flight)).

### What happens to my data when a sandbox is deleted? [#what-happens-to-my-data-when-a-sandbox-is-deleted]

Deleting a sandbox, by hand or at the end of its lifetime, erases its disk, memory, and environment variables with no undo. What the workspace keeps after a delete, and what erasing the workspace removes, is on [Data retention](https://prized.dev/docs/data-retention#records-retained-after-deletion).

## Pricing and limits [#pricing-and-limits]

### How much does it cost? [#how-much-does-it-cost]

Per second, with no minimum: running, by vCPU, memory, and disk; paused, by disk and saved memory alone ([Billing: Sandboxes](https://prized.dev/docs/billing#sandboxes)).

vCPU: $0.04 per vCPU-hour running; paused, not charged. Memory: $0.0125 per GB-hour running; paused, $0.0001 per gb-hour, for the saved memory. Disk: $0.0001 per GB-hour running; paused, $0.0001 per gb-hour. 1 vCPU, 2 GB, 10 GB disk: $0.066 an hour running, $0.0012 an hour paused. 2 vCPU, 4 GB, 10 GB disk: $0.131 an hour running, $0.0014 an hour paused. 4 vCPU, 8 GB, 10 GB disk (the default): $0.261 an hour running, $0.0018 an hour paused. 8 vCPU, 16 GB, 10 GB disk: $0.521 an hour running, $0.0026 an hour paused.

### What do I get for free? [#what-do-i-get-for-free]

New workspaces get $30 of free credit with no card. On the free credit alone you can run 4 sandboxes at once, each up to 2 vCPU, 4 GB, and 60 minutes, so a free fork is a parent plus 3 copies; a [top-up](https://prized.dev/docs/billing#topping-up) or a plan lifts the workspace to the full quotas ([Free tier](https://prized.dev/docs/sandboxes#free-tier)).

### How long can a sandbox live, and what does pausing do? [#how-long-can-a-sandbox-live-and-what-does-pausing-do]

Up to 24 hours from the create, paused time included (60 minutes on the free tier), then it is deleted. A paused sandbox keeps its memory and disk and bills for storage alone, and on resume every process carries on where it stopped ([Pause and resume](https://prized.dev/docs/sandboxes#pause-and-resume)).

### What happens at a limit, or when my credit runs out? [#what-happens-at-a-limit-or-when-my-credit-runs-out]

A request past a quota makes nothing and answers `429 sandbox_quota_exceeded`, naming the limit in `reason` ([Limits: Sandboxes](https://prized.dev/docs/limits#sandboxes)). At a zero balance, with overage off, running sandboxes pause until you add credit and resume them, and are still deleted when their lifetime ends ([Billing: Sandboxes](https://prized.dev/docs/billing#sandboxes)).

## What's not there yet [#whats-not-there-yet]

### Can I bring my own image? [#can-i-bring-my-own-image]

Not yet: no templates from your own Dockerfile or image, and no saving a sandbox as a template. Install what you need once in a sandbox, then [fork](https://prized.dev/docs/sandboxes#fork) it for each job.

### Is there an SDK? [#is-there-an-sdk]

No SDK packages are published yet. Use the [Sandbox API](https://prized.dev/docs/sandboxes-api) from any HTTP client, a [helper for Python or TypeScript](https://prized.dev/docs/sandboxes-python-typescript), or `prized sandbox` from the [CLI](https://prized.dev/docs/cli#sandboxes).

### Can I stream a command's output? [#can-i-stream-a-commands-output]

Not yet: an exec answers when the command ends, with up to 4 MiB of each stream. For a long job, write its output to a file and read it with a later exec or a download ([Run a command](https://prized.dev/docs/sandboxes-api#run-a-command)).

### What else is missing? [#what-else-is-missing]

Other regions, GPUs, egress allow and deny lists, SSH or a terminal into a sandbox, preview links to its ports, more than 8 vCPU or 16 GB, and lifetimes past 24 hours. [Not yet](https://prized.dev/docs/sandboxes#not-yet) lists each with what to use instead.

## Getting help [#getting-help]

### Where do I get help? [#where-do-i-get-help]

Email the support address shown on https://prized.dev/docs/troubleshooting with the sandbox id and the error from the response; common errors and their fixes are on [Troubleshooting: Sandboxes](https://prized.dev/docs/troubleshooting#sandboxes). Report a vulnerability to the same address, before publishing it if you can ([Security and trust](https://prized.dev/docs/security#certifications-and-disclosure)).