Inbox Zero vs Mailstrom

Inbox Zero

• Gmail and Outlook users who want mail sorted and replies drafted for them
• Teams that prefer open source software they can inspect or self-host
• Clearing newsletters and cold outreach out of a crowded inbox

Mailstrom

• Clearing thousands of old messages out of a neglected inbox
• People who want to choose what goes themselves instead of relying on AI sorting
• Cleaning several mailboxes: Pro covers 20 email accounts

Inbox Zero

• There is no free plan for the hosted service: every plan starts with a 7-day trial that needs a credit card.
• It supports Gmail, Google Workspace and Microsoft Outlook accounts only.
• The AI meeting notetaker, Slack and app integrations, email digests and auto-filed attachments start at Plus.
• The free Inbox Zero Tabs browser extension works with Gmail only, and the mobile apps leave some settings to the web app.

Mailstrom

• It runs in the browser only; the site lists no mobile or desktop apps.
• The free trial is a one-time snapshot of up to 5,000 messages, and only 25% of them can be deleted, archived or moved.
• It works over IMAP, so POP-only accounts and Exchange servers without IMAP enabled cannot be connected.
• Basic is capped at 1 email account and 10,000 emails, and the FAQ says folders other than the inbox cannot be organized yet.

Inbox Zero

AI labels and plain-English rules

Incoming mail is sorted into categories such as To Reply, Newsletter, Marketing and Cold Email. You can add categories of your own and describe in plain English how the assistant should handle mail.

Pre-drafted replies

Emails that need a response get a draft written in your tone, based on your email history and calendar, waiting in the inbox for you to review and send.

Bulk unsubscribe and archive

Shows which senders you never read so you can unsubscribe from and archive them in one click. A cold email blocker and email analytics are part of every plan.

Optional email client

A keyboard-first client for Gmail and Outlook on web, desktop and iPhone, with a split inbox, a command palette, several accounts in one inbox and team comments that are never sent as email.

Chat from Slack and Telegram

The assistant can be reached from Slack or Telegram to read mail, draft replies and manage the inbox. The pricing page lists the Slack integration from the Plus plan.

Open source and self-hosting

The code is public on GitHub, with the web and desktop email client under the AGPL license. The docs cover self-hosting with Docker, on Vercel, AWS or Kubernetes.

Mailstrom

Bundles of related mail

Groups inbox messages by sender, subject, date and size so that tens, hundreds or thousands of them can be deleted, archived or moved to a folder in one action.

Unsubscribe

From the Mailing Lists tab, Unsubscribe sends a request email to the list owner. If the list gives no unsubscribe address, its web page opens in a new tab instead.

Block

Removes the selected messages and creates a rule that keeps future mail from the same sender, mailing list or subject out of the inbox. Available to subscribers.

Chill and Expire

Chill takes messages out of the inbox and returns them on a date you choose. Expire removes mail from a sender or mailing list after a set period. Both need a subscription.

Automatic move rules

A move can be saved as a rule, so future messages that match a sender or subject are filed into the chosen folder as they arrive. Subscribers' mail is loaded continuously.

Undo and task history

Actions are carried out by your email service and are not permanent: deleted mail goes to its trash, and an Undo feature reverses any command from the task list.

Inbox Zero

• Starter$18

  per user / month, billed annually; $20 billed monthly

  Sorts and labels every email, drafts replies in your voice, blocks cold emails, bulk unsubscribe and archive, email analytics and pre-meeting briefings.

• Plus$28

  per user / month, billed annually; $35 billed monthly

  Adds 2 email accounts per user, the AI meeting notetaker, Slack and app integrations, email digests, auto-filed attachments and an unlimited knowledge base.

• Professional$42

  per user / month, billed annually; $50 billed monthly

  Everything in Plus, plus team-wide analytics, priority support and a dedicated onboarding manager.

• EnterpriseCustom

  SSO, SCIM, on-premise deployment and a dedicated account manager, arranged with the sales team.

Mailstrom

• Basic$9

  per month, or $59.95 per year

  1 email account with up to 10,000 emails, 200 smart filters, unlimited email removal, and Chill, Expire and Block.

• Plus$14

  per month, or $99.95 per year

  3 email accounts with up to 250,000 emails and 400 smart filters.

• Pro$29.95

  per month, or $199.95 per year

  20 email accounts with unlimited inbox size and 1,000 smart filters.

Inbox Zero

• Annual discount

  Save up to 20% with annual billing

  Annual billing lowers Starter from $20 to $18, Plus from $35 to $28 and Professional from $50 to $42 per user a month. The pricing FAQ puts the saving at up to 20%.

• Education

  Student discount on request

  The pricing FAQ says students can email the company to have a discounted plan set up. The size of the discount is not published.

• Nonprofit

  Nonprofit and open-source project discounts

  The same FAQ answer covers nonprofits and open-source projects, which can email for a discounted plan. No rate is published.

Mailstrom

• Annual discount

  Annual plans are marked as saving 40%

  The subscribe page labels annual billing as saving 40%: Basic is $59.95 a year against $9 a month, Plus $99.95 against $14 and Pro $199.95 against $29.95.