Add Fuzziness to Calendar Dates

Looking to add a bit of randomness to your date data? The Add Fuzziness to Calendar Dates tool lets you introduce variability to each date by shifting it randomly forward or backward by a few days. It’s great for anonymizing records, simulating real-world variations, or testing how your app handles imperfect date inputs.

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Supported file types: .txt, .csv, .log, .json, .md, .xml, .html
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How to Use:

  1. Paste your list of dates in YYYY-MM-DD format into the input box.
  2. Choose the Max Fuzziness range (in days) using the Options box.
  3. Each date will be randomly adjusted forward or backward within the selected range.
  4. You can also import a file using the Choose File button.
  5. Use Copy Output or Export to File to save your randomized date list.
  6. Press Clear All to reset everything.

What Add Fuzziness to Calendar Dates Tool can do:

This tool takes structured calendar dates and applies a fuzzy shift to each one. By randomizing dates within a controlled range, you can simulate imperfect entries, obscure sensitive time data, or add realism to datasets for training or testing purposes.

Example:

Input:

2024-12-25
2000-01-01
2025-05-18
1999-07-04

Max Fuzziness: 3 days

Possible Output:

2024-12-27
1999-12-31
2025-05-16
1999-07-03

Common Use Cases:

Perfect for data privacy, natural variability in simulations, or testing systems with real-world inconsistencies. It’s especially useful for healthcare, education, and log-based data where dates need to remain realistic but non-specific.

Useful Tools & Suggestions:

If you’re going for unpredictability, Add Errors to Calendar Dates takes it further with more chaotic tweaks. And to see how fuzziness plays out over time, Generate Random Date Intervals gives you a solid pool to test with.

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