# Depth chart

A React component in [Beamline](https://beamline.io/)'s [Trading](https://beamline.io/components/trading) category. Live demo: https://beamline.io/components/depth-chart

Cumulative bid and ask depth as stepped areas around the mid, with hover readout.

## Use it for

- Showing how much size sits within a price range.

## Not for

- Picking a price level → [order-book](https://beamline.io/components/order-book).

## Anatomy

- bid area + line
- ask area + line
- mid line
- size axis
- price axis
- readout

## Variants

- **range**: fraction of mid

## States

- live
- hover
- empty (no bids and no asks: says so instead of drawing)
- hover (readout names the side in words)
- empty
- RTL (price axis stays left to right)

## Keyboard

- Presentational SVG with a text summary (role=img aria-label).

## Motion

None: the areas redraw in place on each book update; the hover readout follows the pointer instantly. Marks take the look's line weight and fill finish (dots in mono, hatching in ink), never an animation.

## Props

| Prop | Type | Default | Description |
| --- | --- | --- | --- |
| `bids / asks` (required) | `Level[]` | — |  |
| `range` | `number` | `0.01` |  |
| `height` | `number` | `220` |  |
| `style / ref` | `CSSProperties / native Ref` | — |  |
| `classNames` | `DepthChartClassNames` | — |  |

## Dependencies

`d3-scale`, `d3-shape`

## Import

```tsx
import { DepthChart } from "@/components/depth-chart/depth-chart";
```

## Get it

Depth chart is part of Beamline: 190 React components and screens your coding agent (Claude Code, Codex, Cursor or any MCP client) installs into your app through Beamline's MCP server, as a ready-built package or as plain React source you can change. $49 one payment (regular $200), no subscription, a year of updates, one licence for your whole team. [Get Beamline](https://beamline.io/checkout?pack=complete) · [Connect your agent](https://beamline.io/connect)

## More in Trading

- [Funding countdown](https://beamline.io/components/funding-countdown): Perpetual funding rate with who pays, and a live countdown ring to the next funding.
- [Market heatmap](https://beamline.io/components/market-heatmap): Treemap of markets sized by weight and coloured by change, grouped by sector, with hatched no-data tiles.
- [Order book](https://beamline.io/components/order-book): Asks, spread and bids with cumulative depth bars, grouping, change flashes and keyboard price picking.
- [Order ticket](https://beamline.io/components/order-ticket): Buy/sell order entry with limit, market and stop types, % of balance, inline validation and a live cost summary.
- [Positions table](https://beamline.io/components/positions-table): Open positions with live unrealised PnL, liquidation warnings and close actions.
- [Price chart](https://beamline.io/components/price-chart): Candles, line or area price chart with volume, OHLC legend and reference lines, built for live ticks.
- [Price ticker](https://beamline.io/components/price-ticker): Symbol, last price with a directional flash, 24h change and stats.
- [Ticker tape](https://beamline.io/components/ticker-tape): A continuously scrolling row of symbols with price, change and mini trend; pauses on hover and focus.
- [Trades tape](https://beamline.io/components/trades-tape): Recent trades, newest first, with side glyphs, large-print marking and one-time arrival flashes.
- [Watchlist](https://beamline.io/components/watchlist): A selectable, sortable list of markets with mini trends, prices, changes and stars.