Extract Integers from Data

Smart mode applies extra rules after the regex: thousand separators are stripped (1,234,567 → 1234567), decimal tails are dropped (45.99 → 45), and the minus sign is honored only when preceded by a non-word character. Strict mode is the original naive behaviour: every run of digits is one integer, decimals split into two integers, and any - in front of a digit run becomes a minus sign. Use Strict when you specifically want every digit cluster – Smart for everything else.

In Smart mode: thousand-separated integers (1,234,567), plain integers (42), and the integer portion of decimal numbers (45.99 → 45). In Strict mode: every run of decimal digits, plus the optional preceding minus sign. Hexadecimal (0x1A), octal (0o17), binary (0b101), and scientific notation (1e5) are not parsed as numeric literals – they’re treated as digit runs (so 0x1A → 0 and 1 in either mode).

Smart mode requires the minus sign to be preceded by a non-word character (whitespace, punctuation, or start of input). So Score: -5 extracts -5, but 2024-01-15 doesn’t extract -1 or -15 because the minus signs are preceded by digits. Strict mode treats every - in front of digits as a minus sign – useful if you actually want that, mostly a footgun otherwise.

Internally each extracted integer is parsed with parseInt, which produces a Number. JavaScript’s safe integer range is ±2⁵³−1 (about ±9×10¹⁵) – values beyond that lose precision. The output preserves whatever parseInt returned, so most real-world inputs are fine, but a 30-digit integer in your text will be rounded.

If “Unique only” is on, duplicates are removed via a Set (order of first appearance preserved). The stats line shows both the total count and the unique count regardless of the toggle, so you can see how many duplicates exist in your input.

Three: List (custom separator – newline, comma, or space), CSV (comma-and-space-separated as a single line), or JSON array ([1,2,3]). The stats line and download extension adapt to the choice. JSON downloads as .json, CSV as .csv, List as .txt.

The regex is O(n) and the post-processing is O(matches). A 10 MB text file finishes in well under a second. The 200 ms input debounce makes typing-while-editing smooth even on large pasted inputs. The fold-based min/max means no stack-overflow on very large arrays.

No. The page loads three static files (HTML, CSS, JS) and then runs entirely in your browser. Your input never leaves the device – no fetch, no XHR, no analytics, no cookies. You can disconnect from the internet after the page loads and the tool still works.

Yes – free, unlimited, no signup, no watermark. The extracted integers are yours to use anywhere. Attribution to is appreciated but not required.