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Test Data Generator

Generate a realistic contacts CSV with seeded duplicates and messy fields — plus an answer key — so you can test any cleanup tool without risking real data.

Test the cleanup before you trust it with real data

Handing a vendor your customer list to "see what it finds" is a big ask. This generator removes it: the file is realistic — names, companies, phones, dates — but every problem in it was planted on purpose and recorded in the answer key. Run the file through any deduplication or cleanup tool and grade the results against the key.

What gets planted

  • Exact duplicates — straight copies. Any tool should catch these.
  • Typo'd emails — two characters swapped. Exact matching misses these.
  • Name variants — Jonathan vs. Jon, same email. Key-based matching on names misses these.
  • Formatting variants — case and punctuation drift in names and company suffixes.
  • Messy fields — mixed date and phone formats, stray whitespace, Illinois vs. IL, and blanks.

Try it on the free CSV dedupe tool to see what exact matching catches — then run the same file through CleanSmart to see SmartMatch catch the typos and name variants too. The same seed always produces the same file, so results are comparable across tools and runs.