MailMaestro vs Inbox Zero (2026): which should you pick?
As of Nov 13, 2026, MailMaestro and Inbox Zero share a 2.0 GPA, and only MailMaestro has a free plan.
Checked Oct 9, 2026 and Nov 13, 2026 · graded Oct 10, 2026 and Nov 13, 2026 by ToolGPA
MailMaestro grades higher on value for money and the free plan. Inbox Zero grades higher on platforms. They get the same grade on features and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
MailMaestro
AI email writing and inbox assistant for Outlook and Gmail
Inbox Zero
Open source AI email assistant for Gmail and Outlook
Which one is for you
Pick MailMaestro if
- Fits if you answer lots of similar emails in Outlook or Gmail
- Works for teams that want shared templates and one bill, from two seats up
Look elsewhere if
- Tight if you stay free: 3 AI requests a week runs out by Tuesday
- Pricey if you want inbox agents, labels and follow-ups, which are Pro-only at $12 a seat
- Skip it if you want a full email client, as it only adds to Outlook and Gmail
- Watch out: annual plans can't be refunded after purchase, according to the pricing FAQ
- Watch out: the name is in flux, as Flowrite was folded into MailMaestro and its old team moved to a separate product
Pick Inbox Zero if
- Fits if you want your Gmail or Outlook sorted into categories and replies drafted for you
- Works for people who want open-source code they can read through or host themselves
Look elsewhere if
- Not for you if you won't hand over a card to try something, because the 7-day trial needs one
- Skip it if your email isn't Gmail or Outlook, as those are the only accounts it supports
- Pricey if you want a second account, the meeting notetaker or Slack, which start on Plus at $28 a user
- Watch out: the free Tabs extension works with Gmail only, and the phone apps send you to the web for some settings
- Tight if you self-host to avoid paying, as that means running it on Docker, Vercel, AWS or Kubernetes yourself
How we grade them
| 2.0GPAMailMaestroFair | 2.0GPAInbox ZeroFair | |
|---|---|---|
| Value for money | CPro is $12 a seat a month on annual billing ($15 monthly), which sits near the dear end of email tools: the middle is about $8 and the cheaper quarter starts at $3. | DStarter is $18 a user a month billed annually, $20 monthly, where the middle for email tools here is $8 and the dearest quarter starts at $14.99. A second email account, the meeting notetaker and Slack all need Plus at $28, and Professional is $42. |
| Free plan and trial | CFree forever with no card, but only 3 AI requests a week. That's a taste, not a plan you can work on. The Pro trial is 14 days. | DNo free plan on the hosted service, and the 7-day trial asks for a credit card up front, though refunds are offered within 14 days of upgrading. The Tabs browser extension is free, and the code is open source if you'd rather host it yourself. |
| Features | CWrites, replies, rewrites and summarizes, with templates and shortcuts. It lives inside Outlook and Gmail, and the listing shows no standalone client. | CMail sorted into categories like To Reply and Cold Email by rules you write in plain English, replies drafted in your tone, one-click unsubscribe from senders you never read, and an optional keyboard-first client. Its own gaps: Gmail and Outlook accounts only, and phone apps that send you to the web for settings. |
| Ease of use | CNo store rating on record. You add it to your mailbox and connect your account, then learn the templates and shortcuts. | CNo rating on record. You tell it what to do in plain English instead of building filters, but you're connecting accounts, teaching it categories and, if you want the extension or self-hosting, doing that setup too. |
| Platforms and integrations | CA browser and Outlook add-in for one job, with Teams, Zoom and Google Meet listed. No phone or desktop app of its own. | AWeb, Mac, Windows, iPhone, Android and a browser extension. You can talk to the assistant from Slack or Telegram, and it connects to Google Drive, OneDrive, Notion and Stripe. Gmail, Workspace and Outlook are the only accounts it takes. |
| Best for | AI replies inside Outlook and Gmail | an open-source AI assistant for your inbox |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: MailMaestro and Inbox Zero. How we grade
Price against what you get
MailMaestro starts at $12 a month for each person and scores 2.0 out of 4 on features, ease of use and platforms. Inbox Zero starts at $18 a month for each person and scores 2.7.
Inbox Zero scores higher, and starts $6 a month higher: the question is whether the extra is worth that to you. Of the other email apps on the chart, 54 score higher than MailMaestro for less, and 9 score higher than Inbox Zero for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- Inbox Zero is open source and self-hostable, according to its own site.
- MailMaestro also covers templates and text expansion.
- Inbox Zero also covers chat assistant and workflow automation.
At a glance
| MailMaestro | Inbox Zero | |
|---|---|---|
| Pricing | Free plan | Free trial |
| Starts at | $12 per seat / month, billed annually ($15 billed monthly) | $18 per user / month, billed annually ($20 billed monthly) |
| Free plan | 3 AI requests a week to write, reply to and improve emails, plus templates and text shortcuts. | None |
| Free trial | None listed | 7-day free trial on every plan; a credit card is required. Refunds are offered within 14 days of upgrading. |
| Web | ||
| macOS | ||
| Windows | ||
| iOS | ||
| Android | ||
| Browser extension | ||
| Made by | Maestro Labs | Inbox Zero Inc. |
| Price read from | maestrolabs.com | getinboxzero.com |
| Checked | Nov 13, 2026 | Oct 9, 2026 |
Worth knowing
MailMaestro
- Flowrite was acquired and folded into MailMaestro; it is listed here under its current name.
- The free plan stops at 3 AI requests a week; unlimited use needs Pro.
- It works inside Outlook and Gmail; the pages list no standalone email client.
- Annual plans are not refundable after purchase, according to the pricing FAQ.
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.
Key features
MailMaestro
- AI writing and replies
- Writes emails from scratch in several languages, drafts replies from the thread and attachments, and rewrites or polishes selected text.
- Inbox agents
- On Pro, agents label incoming mail, prepare drafts before an email is opened and send follow-ups when someone has not replied.
- Summaries
- Summarizes long emails and threads. Summarizing attachments and asking questions about the inbox are marked as Outlook features.
- Templates and shortcuts
- Magic templates combine saved text with the AI writer, and keyword shortcuts insert details such as a phone number or LinkedIn profile.
- Team management
- With two or more seats, Pro adds shared templates and user management with centralized billing in the Maestro Portal.
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.
Plans
MailMaestro
Free$0
3 AI requests a week, Magic templates, custom text shortcuts, in Outlook and Gmail.
Pro$12
per seat / month, billed annually ($15 billed monthly)
Unlimited writing and replies, auto labels, drafts and follow-ups, summaries. 14-day free trial.
EnterpriseCustom
Company-wide templates, SSO, custom data retention and dedicated support. Billed annually only.
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.
Ways to pay less
MailMaestro
- Annual discount
20% off MailMaestro with annual billing
Pro is $12 per seat a month billed annually at $144, against $15 a month billed monthly, according to the pricing page.
- Other savings
Special pricing for startups, nonprofits, education
The pricing FAQ says Maestro Labs has special pricing for startups, non-profits and education; the terms are not shown on the page.
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.
Common questions
Which is cheaper, MailMaestro or Inbox Zero?
As of Nov 13, 2026, MailMaestro is cheaper to start with: $12 a month for each person, against $18 a month for each person for Inbox Zero. MailMaestro starts at $12 per seat / month, billed annually ($15 billed monthly), and Inbox Zero starts at $18 per user / month, billed annually ($20 billed monthly).
Which has a free plan, MailMaestro or Inbox Zero?
As of Nov 13, 2026, only MailMaestro has a free plan. Inbox Zero does not, though it has a free trial.
Which platforms do MailMaestro and Inbox Zero run on?
As of Nov 13, 2026, only Inbox Zero lists a web app and macOS, Windows, iOS and Android apps. Both list a browser extension. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.