Customize ChatGPT

by https://fumi-nozawa.space · fumi-nozawa.space · Tools

Established publisherManifest V3 Free

View in Chrome Web Store Data as of 16 Oct 2026

A Chrome extension to customize and inject prompts, roles, and guardrails (negative prompts) into ChatGPT.

Users

−1 in 30 days

Rating

0.0 / 5

unchanged in 30 days

Ratings

0 in 30 days

Store rank

#296K

#243K among extensions

Version

1.0

updated 25 Jul 2026

Users

monthly, 3 months

Latest, 16 Oct 2026: 3 usersMove the mouse over the chart for any month

Ratings count

monthly, 3 months

Latest, 16 Oct 2026: 0 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About Customize ChatGPT

Define custom roles — each with its own system prompt and guardrails — and switch between them instantly from your browser toolbar while you chat. ChatGPT's built-in Custom Instructions only let you set one context at a time. Changing it means digging through settings and rewriting everything. This extension puts role switching one click away, making it far more intuitive for anyone who uses ChatGPT across different tasks or contexts. Each role lets you set what ChatGPT should do and what it should avoid. Pick a role, start chatting, switch anytime. Your saved roles stay ready whenever you need them.