Contact
Email is the only channel, and it is read by a person.
Write to josekmani60@gmail.com. There is no contact form here on purpose: a form would need to send your message through a server, and this site is built to avoid that wherever it can.
What to write about
Something is broken
Tell us which tool, what you did, what happened, and which browser you were using. A tool that produces a wrong number or a file that will not open is the highest priority thing we can hear about.
A tool is missing
If you searched for something and did not find it, that is useful to know. Tools get built in the order people actually ask for them.
Anything else
Questions about how a tool works, a correction to something we have written, or a note about the site itself are all welcome.
Please do not send us your files
If a tool is mishandling a document, describe what went wrong rather than attaching the document. We do not want a copy of your files — the whole site is built so that we never receive them, and an email attachment would undo that. A description of the file (its size, how it was created, how many pages) is almost always enough to reproduce the problem.
Before you write
The FAQ at the bottom of each tool page answers most questions about that specific tool, including how its numbers are calculated. The privacy policy covers what happens to files and text, and the about page explains how the site is built and paid for.