Negative Number Dataset Generator

Runs in browser Test Data

Datasets focused on negative inputs: refunds, debits, temperatures and coordinates, with formats like -5, (5), −5 and 5- to test parsers.

TEST DATA ONLY — all generated names, contacts, identifiers and numbers are synthetic and do not belong to real people or accounts.
Privacy: This tool runs entirely in your browser. Your input never leaves your device.

How is a large synthetic dataset generated for testing?

From three decisions: the shape (the fields, their types and the format — JSON, CSV, SQL, XML), the volume (enough rows to exercise pagination, indexes and import limits) and the variety (boundary values, nulls, duplicates, special characters and the odd malformed row a real export contains). A fixed random seed makes the set reproducible, so a failing test can be re-run on the same rows. Format rules matter at volume: CSV fields with commas, quotes or line breaks must be quoted as RFC 4180 describes, and one oversized JSON document behaves very differently from the same rows as JSON Lines.

Read the guide: What is Performance Testing?

How to use Negative Number Dataset Generator

  1. Enter the most and least negative bounds and the number of decimals.
  2. List the sign formats to mix (comma separated).
  3. Press Generate and export.

Negative Number Dataset Generator features

  • Negative integers or decimals in a chosen range
  • Sign formats: -5, (5), −5 (U+2212), 5-, "- 5" and explicit +/−
  • Edge cases: -0, -0.0, INT8…INT64 minimums and the overflow below them, -Infinity, malformed signs
  • Format column so tests know which convention each value uses
  • Seedable; JSON, CSV, SQL, XML, JSON Lines or one-per-line output

Negative Number Dataset Generator example

Accounting and Unicode minus

Input:

Range −1000 to −1 · Decimals: 2 · Formats: parentheses, unicode-minus

Output:

value,number,format
(70.72),-70.72,parentheses
−45.73,-45.73,unicode-minus
-0,0,edge

Frequently asked questions about Negative Number Dataset Generator

Which sign formats can be produced?

Hyphen-minus (-5), accounting parentheses ((5)), Unicode minus (−5, U+2212), trailing minus (5-), a spaced sign (- 5) and explicit plus/minus.

What edge cases are included?

-0 and -0.0, INT8/16/32/64 minimums and the overflow just below them, MIN_SAFE_INTEGER, tiny and huge negatives, -Infinity and malformed signs such as "--5".

Why does the tool refuse positive bounds?

Its job is negative input; set both bounds at or below zero (for example -100000 and -1).

References