All file extensions
.TMP File
What is it?
A .tmp file is a temporary file created by an application or the operating system to hold data during a task — like an unsaved document or a work-in-progress download — normally deleted automatically once the task finishes.
How do I open it?
Rarely useful to open directly; if a program crashed and left one behind, try renaming it to the expected original extension (e.g., .docx) to see if it can recover unsaved work.
Is it safe?
Yes, a .tmp file itself just holds data and can't run code.
Can I delete it?
Generally safe to delete, especially old ones — but close the program that might still be using it first, in case it's actively writing to that file.