> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sailresearch.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Billing Overview

> How Sailbox usage turns into a bill

When you create a Sailbox, you specify the size of the VM. You are eligible to use all the
resources in your VM and you are only charged for observed usage, not capacity. For example, if a Sailbox with a 4 vCPU ceiling
is using 0.01 vCPU, you are charged for 0.01 vCPU. You are not charged at all
while a Sailbox is sleeping, paused, checkpointing, or cold-starting.

## What each size includes

You pick a size at create time: `s`, `m`, or `l`. A size sets the vCPU count
and the default memory and disk ceilings, and it sets the creation charge.
Ceilings cap what a workload may spend; they do not reserve anything, so a
bigger size costs nothing extra while the Sailbox sits idle.

| Size | vCPU | Memory ceiling         | Disk ceiling            |
| ---- | ---- | ---------------------- | ----------------------- |
| `s`  | 1    | 16 GiB (up to 64 GiB)  | 32 GiB (up to 128 GiB)  |
| `m`  | 4    | 32 GiB (up to 128 GiB) | 128 GiB (up to 512 GiB) |
| `l`  | 8    | 64 GiB (up to 256 GiB) | 256 GiB (up to 1 TiB)   |

Pass `memory_limit_gib` or `disk_limit_gib` at create time to set a ceiling,
within the range shown. The default size is `m`. Choose `s` for the fastest
cold starts and resumes; its lower ceilings also cap what a runaway workload
can consume.

## Where to see usage

* **Dashboard.** The Sailboxes page at [app.sailresearch.com](https://app.sailresearch.com)
  shows spend for the period broken down by app and by Sailbox, alongside live
  CPU, memory, and disk utilization. The Billing page holds your credit
  balance and invoices.
* **CLI.** `sail box list` shows each Sailbox's current CPU, memory, and disk
  usage against its ceilings, and `sail box top` is a live view of the same.

## FAQ

<AccordionGroup>
  <Accordion title="Does a bigger size cost more?">
    Only at creation, and only slightly: the creation charge differs by size.
    Ongoing charges follow what the Sailbox uses, so an `l` Sailbox that idles
    at 0.05 vCPU costs the same per hour as an `s` doing the same.
  </Accordion>

  <Accordion title="What does a sleeping Sailbox cost?">
    Nothing. Sleeping, paused, checkpointing, and cold-starting time is not
    billed. Charges resume when the Sailbox is running again.
  </Accordion>

  <Accordion title="Do copies cost the same as new Sailboxes?">
    Yes. A Sailbox started from a checkpoint is a full Sailbox: it pays the
    creation charge for its size and bills for its own usage until it sleeps or
    you terminate it. Clean up a fleet when the work is done.
  </Accordion>

  <Accordion title="What happens when my credits run out?">
    Sail pauses your running and sleeping Sailboxes and blocks anything that
    would add spend: creating, resuming, and running commands. Nothing is
    terminated, and you can still pause and terminate from the dashboard. Add
    credits on the Billing page, then resume the Sailboxes you need.
  </Accordion>
</AccordionGroup>