Slashy vs Superhuman: Which AI Email Client Wins?
Pick Superhuman if you run Outlook or a whole team and want the fastest, most mature email client with AI layered on top; pick Slashy if you are on Gmail and want the AI to do more of the work, drafting in your voice and running automations, on a single $30 plan. Both are email clients you switch into, so neither one works inside the Gmail or Outlook tab you already have open.
The price looks identical at the entry level. What the entry price buys is where they split.
Slashy vs Superhuman at a glance
| Slashy | Superhuman Mail | |
|---|---|---|
| What it is | AI-first email client built around drafting and follow-through | Keyboard-first email client, now part of the Superhuman suite |
| Email providers | Gmail and Google Workspace; Outlook.com and Microsoft 365 in a limited web beta | Gmail and Outlook |
| Apps | Mac, iPhone and web; Android coming soon | iPhone and Android apps, among others |
| Entry price | Professional: $30/user/mo monthly, $25/user/mo billed annually | Starter: $30/member/mo monthly, $25/member/mo billed annually |
| Drafts in your voice | Included on the one paid plan | Auto Drafts on Business: $40 monthly, $33 annually |
| Ask your inbox a question | Plain-language search, included | Ask AI, Business only |
| Automations | Run when email arrives, before a meeting, or on a schedule | Auto labels, auto archive, auto reminders |
| Calendar | Create, move or decline meetings by asking; find times across calendars | Calendar view, share availability, Find Time |
| Chat access | Ask it from iMessage or Slack | Superhuman Go, the suite’s assistant |
| Free option | None; 7-day trial with a credit card | No free Mail plan; the suite’s free tier covers Grammarly, Docs and Go |
How each one works
Superhuman made its name on speed. Everything is a keyboard shortcut, Split Inbox pulls your team, VIPs and tool notifications into their own lanes, and features like Remind Me, Snooze, Snippets and read statuses are built for people who clear hundreds of emails a day. The AI sits on top: Instant Reply, auto labels, auto summaries, and on the Business plan, Auto Drafts and Ask AI. Superhuman’s own page now says its AI can draft “and if you want” send emails for you. Teams get shared conversations, comments and shared drafts. More in our Superhuman review.
Slashy starts from the other end. It learns how you write and who you work with, then prepares replies, summarizes long threads, briefs you before meetings and tracks conversations still waiting on an answer. You can speak a draft instead of typing it, ask a plain-English question to find a thread or attachment, and message Slashy from iMessage or Slack to search, summarize or draft without opening the app. It syncs with Gmail, so your mail and labels stay put, but you read and reply inside Slashy. More in what Slashy is.
The short version: Superhuman makes you faster at your inbox. Slashy tries to do more of your inbox for you.
Pricing: same sticker, different contents
Both start at $30 per user per month billed monthly, or $25 billed annually. Slashy’s annual plan is $300 per user per year.
Slashy has one self-serve plan. Professional includes voice-matched drafts, memory, plain-language search, meeting prep, reminders, automations, calendar management, unlimited inboxes and the iMessage and Slack access. Enterprise adds SSO, SCIM and a dedicated account manager at a custom price. The 7-day trial needs a credit card.
Superhuman splits its AI across two tiers. Starter gets email productivity, “Superhuman AI”, team collaboration and calendar tools. The features most buyers come for, Auto Drafts, Ask AI, custom auto labels, CRM integrations and the Superhuman Mail MCP, are on Business at $40 monthly or $33 annually. Superhuman advertises 15% off annual plans for teams of five or more.
So if drafting in your voice is the reason you are shopping, the real comparison is Slashy at $30 against Superhuman Business at $40. The full tier breakdown is in Superhuman pricing.
One wrinkle on Superhuman’s side: the suite plan also called Business costs the same $33 annually or $40 monthly and bundles Mail with Grammarly, Docs and Go. If you already pay for Grammarly, that changes the math. The naming history is in Superhuman acquired by Grammarly.
Outlook is the first filter
If your mail lives in Microsoft 365, this comparison is nearly over. Superhuman Mail is built for teams on Gmail or Outlook. Slashy’s own FAQ says it works with Gmail and Google Workspace, with Outlook.com and Microsoft 365 support “available in a limited web beta.” A beta on the web only, with no word on the Mac and iPhone apps, is not something to roll out to a team yet.
Switching from Superhuman to Slashy
Slashy is plainly courting Superhuman users. Its settings include a Superhuman connection that imports your Split Inboxes as Slashy labels, so the filing system you built does not have to be rebuilt by hand. Slashy also connects to about twenty tools, including HubSpot, Salesforce, Attio, Notion, Todoist, Google Drive and Sheets, and meeting-note apps like Granola, Fathom, Fireflies and Otter.
Superhuman is heading toward bigger bundles instead. It bought Fathom, the AI meeting notetaker, this September and says it plans to bring Fathom’s notetaking into its platform. Its Go assistant, included across suite plans, is a separate product from Mail.
Where Superhuman wins
- Outlook and Microsoft 365, fully supported today.
- Speed and polish. Years of keyboard-first design that Slashy has not had time to match.
- Team email. Shared conversations, shared drafts and team read statuses for groups that answer from the same threads.
- Android. Slashy’s Android app is still coming.
Where Slashy wins
- More AI on the entry plan. Drafts in your voice, search by question and automations at $30, not $40.
- Automations with a trigger. They run when email arrives, before a meeting or on a schedule.
- Calendar by request. Tell it to create, move or decline a meeting.
- Reach from chat. Draft or search your mail from iMessage or Slack.
- Unlimited inboxes on one seat.
If you would rather not switch email clients at all
Both tools ask you to move where you read mail. Many people comparing them really want the inbox handled: the client who wants to move Thursday, the follow-up nobody sent, the thread that needs a CRM update. Carly does that from the Gmail or Outlook you already use, over email and text.
- CC it like a person. Each agent has its own email address, so you CC it on a thread the way you would CC an assistant.
- It schedules. It finds times, sends invites and handles reschedules across your calendars.
- It triages and drafts your email without replacing your client.
- It runs on its own. Workflows fire on a new email, a calendar event, a form or a schedule, in the cloud, with no app open.
- It connects to thousands of apps, including HubSpot, Salesforce, Attio, Notion, Slack and Google Sheets.
Setup is describing what you want in plain English. Say a client emails Michael to push Thursday’s call: he CCs Carly, which checks his calendar, offers new times, sends the updated invite and logs the change in HubSpot. Free Zapier-style workflows; AI agents from $35/month. Get started with Carly.
FAQ
Is Slashy cheaper than Superhuman? At the entry level they cost the same: $30 per user per month billed monthly, or $25 billed annually. Slashy includes voice-matched drafts and plain-language search at that price, while Superhuman’s Auto Drafts and Ask AI need its Business plan at $40 monthly or $33 annually.
Does Slashy work with Outlook? Partly. Slashy works with Gmail and Google Workspace, and its FAQ says Outlook.com and Microsoft 365 support is in a limited web beta. Superhuman Mail supports both Gmail and Outlook.
Can I move from Superhuman to Slashy? Yes. Slashy syncs with your existing Gmail account, so nothing migrates, and it can import your Superhuman Split Inboxes as labels.
Do Slashy or Superhuman work inside Gmail? No. Both are separate email clients that sync with your account. You read and reply inside their apps, not in the Gmail web interface.
Who owns Superhuman now? Grammarly bought Superhuman in 2025 and then renamed the whole company Superhuman. Superhuman Mail is the email app; the same company also runs Grammarly, Docs, Go and, since September 2026, Fathom.
Related: Slashy alternatives · Superhuman alternatives · Shortwave vs Superhuman · Fyxer vs Superhuman · Superhuman vs Shortwave vs Carly
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