Result
All calculations run locally in your browser: parsing, chart, export. Disconnect the network and the page keeps working.
Facts and limits of this method
| Match rule | A line matches if it contains at least one letter а–я, ё, А–Я or Ё |
|---|---|
| Default direction | Lines with at least one Cyrillic letter are kept |
| Invert mode | Lines with no Cyrillic letters at all are kept instead |
| Character set | Standard Russian Cyrillic alphabet, including ё/Ё |
| Order | Matching lines keep their original relative order |
| Processing | Runs locally in the browser; nothing is uploaded |
When it misleads you
- The check covers the standard Russian Cyrillic alphabet, а through я plus ё. Letters used only in other Cyrillic-based alphabets (Ukrainian і/ї/є, Belarusian ў and similar) are not included in this set.
- Digits, punctuation and spaces are ignored — a line made only of numbers and symbols, with no letters at all, never matches, in either direction.
- A line mixing scripts, like "Invoice 20241" written next to Cyrillic text, matches only if it also contains at least one actual Cyrillic letter somewhere, not because of the digits.
- This is a line-level filter: it decides whether the whole line stays or goes, it does not extract or highlight just the Cyrillic portion of a mixed line.
How it is calculated
The text is split into lines on every line break. Each line is tested against a simple rule: does it contain at least one character from а-я, ё, А-Я or Ё?
By default, lines that pass the test are kept, and the rest are dropped. With invert switched on, the logic flips: lines with no Cyrillic letters are kept, and lines with any Cyrillic letter are dropped.
The surviving lines are re-joined with a single line break each, preserving their original order from the input.
The counter reports how many lines matched the active rule, whichever direction is selected.
Questions and answers
Does it detect letters from other Cyrillic-based alphabets?
Only the standard Russian Cyrillic alphabet is checked. Letters unique to other Cyrillic alphabets, like the Ukrainian і or the Belarusian ў, are not part of this set.
What happens to lines with a mix of scripts?
Any line with at least one Cyrillic letter matches, even if the rest of the line is in Latin script — the check only needs one qualifying character.
How do I get the lines that have NO Cyrillic letters instead?
Turn on the invert option. The tool then keeps every line with zero Cyrillic letters and drops the ones that have at least one.
Will digits or numbers make a line match?
No, digits are not letters. A line made only of numbers and punctuation, with no actual letters, never matches this filter.
Is my text uploaded anywhere?
No. Everything runs in your browser and the text never leaves your device.