What does Keep Alnum do that other Developer pages on this site do not?

Keeps only ASCII letters and digits; reports lengths. Short version: Keep A–Z / 0–9; lengths before/after.

Does Keep Alnum upload my file or text to Tool-You servers?

No. Keep Alnum runs in this browser tab. Files stay on the device. Limit note: Empty input fails.

Should I use Strip Punctuation instead of Keep Alnum?

Use Keep Alnum when you need Keep A–Z / 0–9; lengths before/after. Use Strip Punctuation when you need Strip punctuation; lengths before/after. They share a category (Developer) but not the same job.

What are the limits of Keep Alnum?

Empty input fails. Also: Keeps only ASCII letters and digits; reports lengths.

Keep Alnum

Keep A–Z / 0–9; lengths before/after.

Keeps only ASCII letters and digits; reports lengths.

What Keep Alnum does

Keeps only ASCII letters and digits; reports lengths.

The interactive controls for Keep Alnum load after this article so crawlers still read the instructions. Path /developer/keep-alnum is the canonical address. Work happens on this device; Tool-You does not take a copy of the file or pasted text for Keep Alnum.

How to use Keep Alnum

Keep this tab on Keep Alnum (/developer/keep-alnum). Pasting into the wrong Developer tool (for example Strip Punctuation) changes the job.
Paste or type the input Keep Alnum expects. Path hint: developer · keep alnum. Keep A–Z / 0–9; lengths before/after.
Apply the Keep Alnum action only. Safe Filename is a different transform (Replace illegal filename characters; length, case, spaces.). Keeps only ASCII letters and digits; reports lengths.
Copy the output of Keep Alnum if you need it elsewhere. Size/complexity still follows: Empty input fails.
If the text job is actually Strip punctuation; lengths before/after., leave Keep Alnum and open Strip Punctuation.

When not to use Keep Alnum

Skip Keep Alnum when a neighbor tool matches better — start with Strip Punctuation or Safe Filename — or when the description already warns the job will fail. In the tool’s own words: Keeps only ASCII letters and digits; reports lengths.

Questions about Keep Alnum

What does Keep Alnum do that other Developer pages on this site do not?: Keeps only ASCII letters and digits; reports lengths. Short version: Keep A–Z / 0–9; lengths before/after.
Does Keep Alnum upload my file or text to Tool-You servers?: No. Keep Alnum runs in this browser tab. Files stay on the device. Limit note: Empty input fails.
Should I use Strip Punctuation instead of Keep Alnum?: Use Keep Alnum when you need Keep A–Z / 0–9; lengths before/after. Use Strip Punctuation when you need Strip punctuation; lengths before/after. They share a category (Developer) but not the same job.
What are the limits of Keep Alnum?: Empty input fails. Also: Keeps only ASCII letters and digits; reports lengths.