Superhuman is a keyboard-first client built around speed, and it is very good at that. It is also a place you have to live: the value arrives when you are inside it. Klorn's output is the opposite — a decision about what deserved to interrupt you, delivered wherever you already read mail.
| Axis | Klorn | Superhuman |
|---|---|---|
| Core promise | Fewer interruptions | Faster processing of the same volume |
| Where you use it | Web, macOS, Windows — or as labels inside the client you already use | Its own client, on macOS, iOS and web |
| Why it decided that | Shown on every row | Rules you configure; AI features are not explained per message |
| Acting unattended | Approval-gated. Send, delete and forward each require a signed receipt pinned to a payload hash | Auto Drafts prepare replies for your review |
| Source & hosting | AGPL-3.0, self-hostable end to end | Closed, cloud only |
| Your own model key | Yes — bring your own key, or run a local model | Not offered |
| Published price | $8.99/mo web · $9.99 native | $30/mo Starter · $40 Business |
Halving the time each email takes is a real gain, and Superhuman earned its reputation delivering it. But it is a multiplier on a number you did not choose. If four hundred messages arrive, a faster client means you process four hundred messages faster.
Klorn works on the number instead. Each message gets exactly one classification into five lanes, and most of the time that classification is a quiet one — filed, visible when you look for it, no notification. The measure of success is not how quickly you cleared the inbox; it is how few times it asked for you.
Grammarly acquired Superhuman in July 2025 and, in October 2025, renamed the whole company Superhuman. The email client is now one surface of a larger AI productivity platform alongside Docs and Grammarly's writing tools. Whether that is good or bad depends on what you want; it is worth knowing before you compare roadmaps.
What we are not claiming. No speed comparison has been run. Superhuman's own published figures are its own; we have not verified them and do not repeat them as ours.
Klorn is also not trying to be a better client than Superhuman. If a fast, beautiful keyboard-driven mail client is the thing you want, Superhuman is the one that has spent ten years on it.