Free · Productivity · 5 of 6 tools · updated Oct 17, 2026
Free AI tools for email writing & inbox management
Gemini is the strongest tool for email writing & inbox management you can use without paying, at 70/100. What you get for nothing: Google AI Pro $19.99/mo. 5 of the 6 tools tracked for this job have a free tier, an open-source licence, or are free outright. It is also the top-ranked tool for this job overall, free or not.
Same evidence score as the ranking — GitHub stars, Hacker News mentions, release activity, free access — recomputed nightly, never sold. See all 6 tools for email writing & inbox management.
Top 3
evidence / 100
+ Deep Research produces long cited reports from dozens of sources, and it reads your Gmail, Drive and Calendar directly when you allow it.
− Quality swings between Flash and Pro models, and it refuses or hedges on some topics more than competitors.
+ Works in nearly every text field on every platform, so corrections and tone suggestions follow you into Gmail, Slack and Word.
− Suggestions can flatten a distinctive voice and the premium nag prompts in the free tier are constant.
+ Works inside the Office apps you already use, drafting Outlook replies, summarizing Teams meetings and turning Word docs into PowerPoint decks.
− Results inside Excel and PowerPoint are often shallow compared with the standalone chat, which makes the $30 business seat hard to justify.
All 5, side by side
| Tool | Score | Pricing | What you get free | Platforms |
|---|---|---|---|---|
| Gemini | 70 | Free tier | Google AI Pro $19.99/mo | web, ios, android, api |
| Grammarly | 23 | Free tier | Pro from $12/mo billed annually | web, mac, windows, ios, android, chrome-extension |
| Microsoft Copilot | 23 | Free tier | Copilot Pro $20/mo; Microsoft 365 Copilot $30/user/mo | web, windows, mac, ios, android |
 Shortwave | 20 | Free tier | no limits published | web, mac, ios, android |
 Lavender | 15 | Free tier | Starter $29/mo | chrome-extension, web |
A free tier counts, and so does an open-source licence you can self-host — both are in the table, so a tool that is only free for a trial is not here.
Head to head: Gemini vs Grammarly Gemini vs Microsoft Copilot Grammarly vs Microsoft Copilot