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

# Volume bars

> Bars that close after a configured quantity of the base asset has traded.

A volume bar accumulates the `quantity` of each aggTrade and closes when cumulative base-asset volume reaches the configured threshold.

```text theme={null}
cumulative_quantity += quantity
close when cumulative_quantity >= threshold
```

The threshold is denominated in the product's base asset. For BTCUSDT, a threshold of `100` means approximately 100 BTC of aggregated trade quantity per completed bar.

## Threshold overshoot

Meridian does not split the threshold-crossing aggTrade. Completed `coin_volume` can therefore be slightly greater than the configured threshold.

## Query example

```json theme={null}
{
  "exchange": "binance-futures",
  "product": "BTCUSDT",
  "bar_type": "volume",
  "begin": "2026-01-01T00:00:00Z",
  "end": "2026-01-02T00:00:00Z",
  "threshold": 100,
  "limit": 1000
}
```

Volume bars make activity comparable in base-asset terms. Dollar bars are usually more appropriate when the analysis needs comparable notional through large price changes.