# PatternBench guides and demonstrations

Learn PatternBench tasks, handle common problems and practise with checked demonstrations using sample data.

Source: https://help.smartfact.ai/patternbench

Read a guide below, or use the help page to ask a general product question. Interactive demonstrations run on desktop and laptop computers. Written instructions work on any device.

## Guides and help pages

- [Inspect captures and preview a replacement](https://help.smartfact.ai/patternbench/guides/captures-and-replacement): Find two item codes, inspect their named captures and preview a replacement without changing the source.
- [Check values that should and should not match](https://help.smartfact.ai/patternbench/guides/expected-cases): Use positive and negative cases to check a whole-code pattern, with fresh regex state for each value.
- [Extract selected captures as JSON](https://help.smartfact.ai/patternbench/guides/extract-values): Choose one named capture and download only those values, preserving leading zeroes.
- [Read a compile error and recover with a corrected pattern](https://help.smartfact.ai/patternbench/guides/pattern-refusal): Keep the source text while correcting an invalid expression, then check fresh results.