Tools for reverse engineering file format?

Question

reverse engineering

Good day!
I want to understand the format of the output files of a proprietary program.
Please tell me the tools.
At the moment I'm using a Hex editor, changing different values ​​in the program and writing down what changes where in the output file and trying to pick up data types (int / byte / char, etc. to get something intelligible).
The output file itself is binary. Please tell me the tools to speed up the process.

Answer 1

Look here: https://www.linux.org.ru/forum/general/11137439
There is binwalk, the utility analyzes a binary file and shows its structure.
Look for programs like this.

Answer 2

no one canceled the classics
https://www.hex-rays.com/products/ida/
www.ollydbg.de xs
where to get the current / th IDA, I think it should be on the rutraker