MailGPT is a Chrome extension that brings AI writing assistance into Gmail. It can turn rough outlines or meeting notes into emails, rewrite complex passages for clarity, and adjust messages to follow a custom writing style.
The extension uses ChatGPT and Claude capabilities through a Pier20 account, so users do not need separate accounts with the model providers. It is an independent extension rather than an official OpenAI or Anthropic product.
Research basis:
This is a source-based directory listing prepared from public product information; it is not represented as a hands-on test. Last updated August 8, 2026. Read our methodology.
How to use this tool
Install the official MailGPT extension from the Chrome Web Store and verify that the publisher is the Pier20-associated developer shown on the listing.
Create the required free Pier20 account, sign in, and open Gmail in the supported Chrome profile.
Start a draft or reply, then provide a concise outline, meeting notes, or the exact passage that needs rewriting.
Choose the relevant drafting or style action and give explicit instructions for audience, tone, length, and desired next step.
Check recipients, names, dates, factual claims, attachments, confidential information, and commitments before sending the edited email.
Core Features
✓AI email drafting directly inside the Gmail compose experience.
✓Conversion of rough outlines into polished professional messages.
✓Transformation of meeting notes into clear follow-up emails.
✓Rewriting of complex passages to improve clarity and readability.
✓Tone adjustments that can add wit, personality, or a more suitable voice.
✓Custom writing styles controlled through personalized instructions.
✓Access to both ChatGPT- and Claude-powered assistance through one Pier20 account.
✓No separate OpenAI or Anthropic account required to use the extension.
Use Cases
#1Draft an email from bullet points
#2Turn meeting notes into a follow-up
#3Simplify a complex message
#4Adapt an email to a preferred writing style
#5Polish a reply before sending
Frequently Asked Questions
MailGPT is a Chrome extension by the Pier20 team that adds ChatGPT- and Claude-powered drafting and rewriting assistance to Gmail.
Yes. The official Chrome Web Store listing says the extension is completely free to use.
Yes. The developer states that a free Pier20 account is required to start using MailGPT.
No. The store listing says separate OpenAI, ChatGPT, Anthropic, or Claude accounts are not required.
Yes. It can transform a rough outline into a polished email, although users should verify every factual detail before sending.
Yes. Meeting-note transformation into clear, actionable email copy is an advertised feature.
Yes. It can simplify complex wording, improve readability, and adapt a message using custom writing instructions.
The extension is specifically presented as a Gmail inbox assistant; support for other mail services is not stated on the official listing.
No. It is an independent extension developed by the Pier20 team and is not an official OpenAI or Anthropic product.
The current Chrome Web Store disclosure states that the extension does not collect or use user data, but users should still review the latest store disclosure and linked privacy policy.
MailGPT Support Email & Customer service contact & Refund contact etc.
