Contact

Requests, bugs, suggestions — say it directly.

Email serviceonenight@163.com

Before writing, state which tool you used, what you entered, what you expected and what you got. That turns a long thread into a one-message fix. For wrong results, include your browser version.

What is worth reporting

A wrong result. Highest priority. Include input that reproduces it and it gets checked quickly.
A tool you want. Describe the situation, not the implementation — repeated requests get scheduled.
A page problem. A button that does nothing, a broken mobile layout, unreadable text in dark mode.
A documentation error. If an explanation is wrong or an example misleads, point it out.

Response time

This is a small, personally maintained site, so instant replies are not possible. Expect an answer within a week; calculation bugs jump the queue.

Please do not email

Never send real passwords, private keys, access tokens or raw data containing sensitive values. Replace the sensitive fields with placeholders.