# Retention & storage calculator

Work out the disk your traces, logs and metrics need for their retention periods, after compression.

## How it works

Each signal keeps its daily volume for its own retention period. Compression shrinks it, extra copies multiply it, and headroom keeps space free for merges and spikes.

```
disk = Σ(daily × days) ÷ compression × copies × (1 + headroom)
```

## Questions

### What compression should I expect?

Columnar stores like ClickHouse often compress telemetry 5 to 15 times.

### Why add headroom?

Databases need free space to merge data, and traffic spikes fill disks faster than averages suggest.

## Related tools

- [Telemetry cost estimator](https://powertraces.com/tools/telemetry-cost)
- [Log volume estimator](https://powertraces.com/tools/log-volume)
- [Metric cardinality calculator](https://powertraces.com/tools/metric-cardinality)
- [Data transfer estimator](https://powertraces.com/tools/data-transfer)

[All tools](https://powertraces.com/tools)