TL;DR
Superhuman is faster and has better AI Write. Shortwave is a third of the price and better for everything else. For most Gmail users, Shortwave wins on value. For high-volume power users who process 200+ emails/day, Superhuman's speed pays for itself.
Head-to-Head
| Feature | Superhuman | Shortwave |
|---|---|---|
| Price (individual) | $30/mo | $9/mo |
| Raw speed / keyboard density | Best in world | Good |
| AI Write (drafts in your voice) | Best | Good |
| Thread summarization | Good | Best |
| Natural-language search | Good | Best — Ask your inbox |
| Bundled inbox | No | Yes — best in any client |
| Outlook support | Yes | No — Gmail only |
| Free tier | No | Yes (5 AI credits/day) |
| Mobile apps | Best | Good |
| Onboarding | Mandatory call | Self-serve |
When Superhuman Wins
You process 200+ emails daily. Your job is email. You use Outlook (Shortwave can't help you). You want every millisecond of keyboard speed. You want AI-drafted replies matched to your voice at industrial scale. $30/month is a rounding error on your salary.
When Shortwave Wins
You're on Gmail. You want great AI features at a fair price. You miss Google Inbox's bundled lanes. You value the free tier for trial. You care more about thread summaries and search than raw typing speed.
Verdict
For 80% of readers, the right answer is Shortwave — fair price, great AI features, no commitment. For the 20% who live in their inbox all day, Superhuman's price is still worth it. Both are excellent; the choice is really about volume and budget.