Decimal Dataset Generator

Runs in browser Test Data

Amounts with 0–10 decimal places, half-even/half-up rounding cases, very small and very large magnitudes, and locale separators for financial and scientific testing.

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 Decimal Dataset Generator

  1. Set the range, precision and style.
  2. Keep the edge cases on to test rounding and parsing.
  3. Press Generate and export.

Decimal Dataset Generator features

  • Fixed-precision decimals (0–10 places) in any range
  • Plain, currency (grouped with a code) or scientific styles; decimal point or comma
  • 27 rounding and precision edge cases (0.1 + 0.2, 2.675, half-even, 2^53 + 1, Arabic-Indic digits, hex, NaN…)
  • Values emitted as strings so formatting survives export
  • Seedable; JSON, CSV, SQL, XML, JSON Lines or one-per-line output

Decimal Dataset Generator example

Currency amounts with edge cases

Input:

Range 0–10000 · Decimals: 2 · Style: Currency · Currency: SAR · Edge cases: on

Output:

value,note
0.30000000000000004,0.1 + 0.2 in IEEE-754 double
2.675,Rounds to 2.67 (binary) instead of 2.68 with half-up
SAR 1,234.50,

Frequently asked questions about Decimal Dataset Generator

Which rounding edge cases are included?

0.1 + 0.2, 2.675 and 1.005 (binary rounding traps), half-even cases (0.5, 1.5, 2.5), negative zero, 2^53 + 1, very small and very large magnitudes, decimal commas and Arabic-Indic digits.

Why are values emitted as strings?

So formatting survives every export: trailing zeros, thousands separators, currency prefixes and the decimal comma are preserved exactly.

Can I produce currency amounts?

Yes — the currency style adds grouping and a code (SAR 1,234.50); the scientific style emits exponent notation.

References