Best AI Email Writers in 2026: Gmail, Outlook, ChatGPT and Claude Compared

Short answer: Start with the AI writer built into your email app. If you use Gmail, try Help me write. If you use Outlook, try Draft with Copilot. Both work right in the compose window and can pull context from your other emails. Use ChatGPT or Claude when an email needs real thinking: a tricky reply, a hard "no", or a message you want to get exactly right. For most work emails, the built-in tool plus a good prompt is all you need.

Facts below were checked on Google's, Microsoft's, OpenAI's and Anthropic's own help and pricing pages in November 2026. Prices are US dollars and change often.

---

Quick Comparison

Tool	Where it works	Free option	Paid access	Best for
Gmail Help me write	Inside Gmail compose and reply	Some personal Google accounts, depending on country	Eligible Google Workspace or Google AI plan	Fast drafts that use details from your inbox and Drive
Outlook Draft with Copilot	Inside Outlook compose	No	Microsoft 365 Personal ($9.99/mo) or higher, or a Copilot license at work	Outlook users who want drafts and thread summaries in one place
ChatGPT	Separate app, copy and paste	Yes	Plus $20/mo	Tricky replies, rewrites, and trying many versions
Claude	Separate app, plus an Outlook add-in on paid plans	Yes	Pro $20/mo, or $17/mo billed yearly	Careful, natural-sounding writing and long threads

Looking at Grammarly too? We compared it separately in Grammarly vs ChatGPT for Writing.

---

Gmail: Help me write

What it does: Drafts a new email from a short prompt, or rewrites your rough draft. You can then ask for changes like "make it more professional" or "mention the Friday deadline", or use one-click options such as Formalize and Shorten.

Why it's good: Google says Help me write can pull details from your other emails and Drive files, like flight times or booking codes, to make the draft more specific. A Sources button shows which emails and files it used.

Who can use it: Anyone with an eligible Google Workspace or Google AI plan. It's also available on personal Google accounts in some countries.

Watch out for: Check every detail it pulls in. A draft that sounds right can still carry the wrong date from an older email.

---

Outlook: Draft with Copilot

What it does: In Outlook, select the Copilot icon above a new message and choose Draft. Type what you want, and Copilot writes it. You can change the length or tone, or try again, before you select Keep it. You can also select text in an email and ask Copilot to change just that part.

Why it's good: It lives where Outlook users already work, and Copilot can also summarize long threads before you reply.

Who can use it: Microsoft lists Copilot in Outlook with Microsoft 365 Personal, Family (subscription owner only) and Premium, and with Copilot business plans. At work, your IT admin controls access.

Watch out for: In new Outlook and Outlook on the web, Draft with Copilot doesn't work on plain-text messages. Switch your compose format to HTML in settings.

---

ChatGPT

What it does: You paste in the email you got, or describe what you need, and ChatGPT writes a reply. It is great at giving you three versions to pick from.

Why it's good: It's free to start and very flexible. It handles the hard emails well: pushing back on a client, asking for a raise, or saying no without burning a bridge.

Who can use it: Anyone. The Free plan works for occasional emails; ChatGPT Plus is $20/month.

Watch out for: It doesn't see your inbox unless you paste things in. Remove names and private details before pasting work emails into a personal account.

---

Claude

What it does: Same idea as ChatGPT: paste the thread, explain the goal, get a draft. On paid plans, Anthropic also lists Claude for Microsoft Outlook.

Why it's good: Claude tends to write in a calm, natural tone that needs less editing to sound like a person. It also handles long threads well.

Who can use it: Anyone on the Free plan. Claude Pro is $20/month, or $17/month billed yearly, and includes the Outlook add-in.

Watch out for: The same rule as ChatGPT: be careful what work data you paste into a personal account.

---

A Simple Workflow for Any AI Email Writer

1. Say who it's for. "My manager", "a new client", "the whole team".
2. Say what you want them to do. Approve, reply by Friday, join a call.
3. Give the key facts. Dates, numbers, names. AI can't guess these.
4. Set the tone. Friendly, formal, firm, short.
5. Edit before you send. Read it out loud. Cut anything you wouldn't say.

---

Prompts You Can Copy

Follow-up after no reply:

Write a short, polite follow-up to a client who hasn't replied to my proposal sent 8 days ago. Ask if they have questions and offer a 15-minute call this week. Keep it under 80 words.

Saying no:

Write a friendly email declining a meeting request from a vendor. I'm not interested right now but want to keep the door open for next year. No more than 4 sentences.

Escalating a problem:

Write a firm but polite email to our IT support team. My laptop issue has been open for 2 weeks with no update. Ask for a fix date and say it's blocking my work.

Rewriting your draft:

Here's my draft. Make it clearer and shorter, keep my meaning, and don't add anything new: [paste draft]

Replying to a long thread:

Here's an email thread. Summarize what's being asked of me in 3 bullets, then draft a reply that answers each point: [paste thread]

---

Which Should You Use?

• You live in Gmail: start with Help me write.
• You live in Outlook and have Microsoft 365 with Copilot: start with Draft with Copilot.
• You need to get a hard email exactly right: use ChatGPT or Claude and ask for three versions.
• Your company has rules on AI: use the tool they approved, signed in with your work account.

---

Frequently Asked Questions

What is the best free AI email writer?

ChatGPT and Claude both have free plans that write good emails if you paste in the context. Gmail's Help me write is also available on some personal Google accounts, depending on country.

Does Gmail have an AI email writer?

Yes. It's called Help me write. It drafts new emails and rewrites your drafts inside Gmail. You need an eligible Google Workspace or Google AI plan, or a personal account in a country where it's offered.

Does Outlook have an AI email writer?

Yes. Draft with Copilot writes and rewrites emails inside Outlook. It's included with Microsoft 365 Personal, Family (owner only) and Premium, and with Copilot business licenses.

Is it safe to use AI to write work emails?

It depends on the account. Built-in tools on a work account follow your company's settings. With personal ChatGPT or Claude accounts, remove names, numbers and private details before pasting, or use the tool your company approved.

Can people tell an email was written by AI?

Sometimes. Overly formal phrasing and filler lines give it away. Give the AI your key facts, ask for short sentences, and edit the draft in your own words before sending.

ChatGPT or Claude for writing emails?

Both work well. Many people find Claude's tone more natural out of the box, and ChatGPT good at quick variations. Try the same prompt in both and keep the one you edit less.

---

Learn to Write Better with AI

• AI for Writing & Content Creation: prompts and workflows for emails, posts and documents
• Automate Emails with AI: templates and automations for repeat emails

Both courses are free, with a certificate when you finish.

---

Facts checked on Google's, Microsoft's, OpenAI's and Anthropic's own help and pricing pages in November 2026. Features, plans and prices change often.