Data Dictionary / Schema Documenter

Datasets ship without documentation; this tool writes it for you. Paste a CSV and get a complete data dictionary — inferred types, fill rates, distinct counts, ranges, and samples — exportable as Markdown, HTML, or JSON.

Data Analytics & Transformation Local processing

Profiling runs locally — samples never leave your browser.

Tool interface

Introduction

Every dataset deserves a data dictionary, but writing one by hand never happens. This documenter profiles your CSV and emits a clean, paste-ready dictionary your team can actually keep next to the data.

How it works

  • Each column is profiled: inferred type, fill rate, distinct count, min/max for numerics, and sample values.
  • The dictionary is rendered in Markdown, HTML, or JSON for wikis, docs sites, or programmatic use.

How to use

  1. Paste CSV (or load the example).
  2. Pick the output format.
  3. Click Generate documentation and copy.

Limitations

  • Sample values are limited to the first three distinct entries per column.
  • Very large CSVs may be limited by browser memory.

FAQ

Is my data uploaded anywhere?

No. Everything runs locally in your browser.

Related tools

Version and changelog

  • Version: 1.0.0
  • Last updated: August 12, 2026
  • Changelog: Initial production release.