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

> ## Agent Instructions
> Spreader is a web service that tracks arbitrage spreads between crypto exchanges. This documentation covers only what a user of the service sees and does.
> Page paths starting with /en/ are English. Translations live under /ru/ and /uk/ with the same file names.
> Screenshots are illustrations. Every screenshot is accompanied by text that states the same facts, so you do not need to see the image.

# Order books

> Live order books of both legs on the spread page: price step, size unit, the marked rows your legs trade at, depth at $5K, and the states when an exchange sends no book.

Order books stream directly from the exchanges into your browser. They need the **Markets** live data source, see [Chart](https://docs.spreader.sh/en/spread/chart.md#live-data-source). In **Server** mode the block says **Books are off in server mode**.

![Two order books side by side with price step, size unit and the In at \$5K bar.](https://mintcdn.com/develops-6bdfff15/wHoc8ymqHXCxymk7/images/spread/books-en-dark.png?fit=max\&auto=format\&n=wHoc8ymqHXCxymk7\&q=85\&s=9641ff5c4de3b939346078f98738bc22)

Two order books side by side with price step, size unit and the In at \$5K bar.

## Layout

Two books are shown side by side: the long leg on the left, the short leg on the right. The marked row in each book is where your leg trades: **Long leg buys at the ask**, **Short leg sells at the bid**. Columns are **Price**, **Size** in the base coin and **Total** in USD or in the coin.

| Control | Meaning |
| - | - |
| **Price step** | Groups levels into buckets of 1× to 100× the market tick. Hyperliquid serves 20 levels per side and aggregates only by powers of ten. |
| **Size in** | Unit of the size and total columns: the coin or USD, shared by both books. |
| **Change market** | Swap this leg for another market of the asset. |

The bar under the books, \*\*In at $5K**, shows the net entry spread for a $5 000 order by the books, with **Buy · ‹exchange› ask** and **Sell · ‹exchange› bid** prices. Hover a row to see **Distance from mid** and **Average price** down to that level.

## States

| State | Meaning |
| - | - |
| **Connecting to ‹exchange›…** | The browser is opening the connection. |
| **Waiting for the book from ‹exchange›…** | Connected, no snapshot yet. |
| **No order book** | The exchange is not sending a book for this symbol right now. It appears as soon as the exchange sends it. |
| **No orders** | The exchange sent an empty book. Trading may be halted. |
| **‹exchange› is unreachable from your browser** | A network filter or your region blocks its connection. Books have no server fallback, the spread keeps running via the server. |
| **No book from ‹exchange›** | This exchange has no browser order book channel yet. Best prices still stream. |
| `only N levels` | The exchange sends fewer levels than the book shows. |

## On a phone

Books are not shown inline. Tap **Books** to open the **Orderbooks** sheet and switch between the two legs with the tabs at the top.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.