Text to Lowercase

The domain part is case-insensitive, but most CRMs and mailing tools compare addresses as plain strings, so [email protected] and [email protected] become two separate subscribers. Normalizing case removes those duplicates before the list is uploaded.

Yes. Case mapping uses the browser's Unicode tables, so Cyrillic, Greek and accented Latin all lower-case correctly. Scripts with no case distinction, such as Chinese, Arabic or Hebrew, pass through untouched.

Nothing — they have no case and stay exactly where they were. Line breaks and tabs are preserved too, so the structure of a list or a CSV fragment survives the conversion intact.

No explicit limit; the tab's memory is the constraint. Tens of thousands of lines convert in a fraction of a second. Split a multi-megabyte file into parts, otherwise the tab may stop responding for a moment while it works.

Not automatically — which letters were capitals is lost for good. Your original stays in the top box until you close the tab, so keep a copy elsewhere if you might need it back later.

Yes. Long-press to paste into the top box, tap convert, then copy, and the result goes to your phone's clipboard. No app to install — a mobile browser is enough. The button labels are in Russian.

No. The script only touches the fields on the open page, writes nothing to browser storage and sends nothing out. Closing the tab discards both the input and the result for good.