Free Sliding Login and Signup Form – Google Apps Script

The second version of the login and signup form, and the one worth taking: it checks what people type, emails them when the account is made, and sends each user to their own destination.

A redirect per user, kept hidden

This is the feature that separates it. The admin assigns each account its own URL, so two people signing in through the same form land in two different places — a student portal for one, a staff dashboard for another. The destination is not revealed in the form, so a user cannot read off the address and bypass the login by going straight there next time.

Signup that refuses bad data

A username already in the sheet is rejected. An email already in the sheet is rejected too — separately, with its own message, so the person knows which one is the problem rather than guessing. And the password must mix an uppercase letter, a lowercase letter and digits; anything weaker is refused. Those three checks are what stop a user table filling with duplicates and one-character passwords within a week of going live.

The welcome email

A successful signup emails the user to confirm their account was created. It is a small thing that makes a form feel like a system, and it gives the user a record they can search for later.

Fitting it to your site

The browser tab title is set in the script — make it your institution's name — and the deployed URL embeds by iframe into Blogger, WordPress or any page you can edit, so the login sits inside your own site rather than on a Google address.