Password Protect Google Sheets – Free Apps Script

Google Sheets sharing is all or nothing: anyone with access sees everything in the file. This puts a password in front of the spreadsheet itself — sheets stay hidden until the right password is entered, with two levels, a lockout and a log of who tried.

How the lock works

On open, every sheet is hidden and a password dialog appears. Nothing is readable until the password is accepted, and you choose which sheets, if any, stay public to everyone. Auto Lock re-locks the file every five minutes, so a sheet left open on an unattended screen closes itself rather than staying open all afternoon.

Two passwords, not one

There is a user password and an admin password. Users get the working sheets; the admin gets those plus the Access Log, which nobody else can see. That separation is the difference between hiding data from a colleague and knowing who has been looking at it.

Against guessing

Three wrong attempts triggers a five-minute lockout, so the password cannot be brute-forced by repeated tries. Every attempt — successful or not — is logged with the timestamp, the Google account email and the type of access, so the record exists whether or not anyone got in.

Setup

The passwords, the number of allowed attempts and the lockout duration are all configurable at the top of the script. There is no add-on to install, no marketplace extension and no subscription — the code is pasted into the sheet's own Apps Script editor.

A practical note: this protects the spreadsheet interface, not the underlying file permissions. Keep the file itself shared only with people who should have it, and use this to control what they see once inside.