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Number regex tester: digits, decimals and money formats
Test digits, signed integers, decimals, money, thousands separators and numbers from 1 to 100. Pick a preset, edit the regex and paste numbers one per line. Copy JavaScript, Python or an HTML pattern when you are ready.
One or more ASCII digits; leading zeros are allowed.
3 of 6 match
- Match
0 - Match
123 - Match
001 - No match
-1 - No match
1.2 - No match
1,000
HTML pattern uses the v flag and applies to text inputs, not type=number. Validate again on the server; Python snippets use ASCII matching to keep digit ranges consistent with JavaScript.
Number regex patterns
Choose a format for your input. Default pattern: ^[0-9]+$. Each preset includes matching and non-matching examples.
| Preset | Regex | Match / no match examples | Notes |
|---|---|---|---|
| Digits only | ^[0-9]+$ | Match: 0, 123, 001No match: -1, 1.2, 1,000; empty string | One or more ASCII digits; leading zeros are allowed. |
| Integer with optional sign | ^[+\-]?[0-9]+$ | Match: 0, +42, -42, 001No match: +, 1.2, 1,000; empty string | ASCII digits with an optional plus or minus sign. |
| Decimal with optional sign | ^[+\-]?(?:[0-9]+(?:\.[0-9]+)?|\.[0-9]+)$ | Match: 12, -12.5, +.5, 0.25No match: ., 12., 1,000; empty string | Allows integers and decimals, including a leading decimal point; requires digits after the point. |
| Money with two decimal places | ^[0-9]+(?:\.[0-9]{2})?$ | Match: 0, 12, 12.00, 001.25No match: -12.00, 12.5, 12.345, $12.00; empty string | Non-negative amounts with either no decimal point or exactly two decimal places; no currency symbol. |
| Thousands separators | ^[0-9]{1,3}(?:,[0-9]{3})*(?:\.[0-9]+)?$ | Match: 1, 123, 1,000, 12,345.67No match: 1000, 1,00, -1,000, 1,000.; empty string | Groups after a comma must contain three digits. Numbers over three digits require commas. |
| Range 1-100 | ^(?:100|[1-9][0-9]?)$ | Match: 1, 9, 10, 99, 100No match: 0, 01, 101, -1; empty string | Whole numbers from 1 through 100, without leading zeros or a sign. |
Number regex in HTML forms
<label for="number-text">Digits</label>
<input id="number-text" name="number" type="text" inputmode="numeric" pattern="[0-9]+" required>A text input can enforce a format with the pattern attribute. HTML matches the entire value using the v flag; add required to reject an empty value. For numeric quantities, type=number supports min, max and step instead of pattern. Validate submitted values on the server.
Number regex FAQ
What regex matches only numbers?
Use ^[0-9]+$ to match one or more ASCII digits. It rejects signs, decimal points, commas and an empty string.
How do I allow decimals?
Choose the decimal preset to allow an optional sign and digits with an optional decimal fraction, or a leading decimal point followed by digits. A trailing decimal point alone is rejected.
Should I use input type=number or a pattern with inputmode=numeric?
Use type=number for numeric values with native min, max and step constraints; pattern does not apply to it. Use type=text with inputmode=numeric and pattern when the exact digit format matters, such as an identifier. Validate on the server too.
How do I match numbers with commas?
The thousands preset accepts groups of three digits after each comma, such as 12,345.67. It rejects malformed groups and unseparated numbers with more than three integer digits.
How do I allow negative numbers?
Choose the signed integer or decimal preset. Each accepts an optional minus or plus sign; the money and thousands presets accept non-negative values only.
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