The Inbox Zero Insider’s Guide
Everything we know about Inbox Zero in one document: what it costs, its grades, getting a refund, getting help and what else to look at. Read it here, or keep a copy.
Inbox Zero
The Insider’s Guide
Open source AI email assistant for Gmail and Outlook
Every plan, grade, refund rule and rival among email apps, read from Inbox Zero’s own pages.
Made by Inbox Zero Inc. · checked Oct 9, 2026 · toolgpa.com
Contents
- 01WelcomeWhat it is, who it suits, its grades and the ten things to know first
- 02What it costsEvery plan, the free plan, ways to pay less and how prices have moved
- 03What it doesIts main features, where it runs, what it works with and who makes it
- 04Where it standsIts grades against its category, and whether to keep it or make your own
- 05The alternativesThe tools it is most often weighed against, side by side
- 06Quick answersThe questions people ask about it, each answered in a line or two
- 07About ToolGPAWho made this guide, what else is on the site, and how to cite it
ToolGPA put this guide together from Inbox Zero’s own pages, its app-store listings and our grades. Every fact in it is on Inbox Zero’s page too, where it is kept up to date. Checked Oct 9, 2026.
Part 01 · Overview
Welcome
What it is, who it suits, its grades and the ten things to know first
2.0
GPA, above 2 of the 51 other email apps we grade
Inbox Zero is an open source AI email assistant that connects to Gmail, Google Workspace and Microsoft Outlook accounts. It labels incoming mail, drafts replies in the user's tone, blocks cold emails and unsubscribes from unread newsletters in bulk, following rules written in plain English. It works in the background of Gmail and Outlook, and it also offers its own email client, mobile and desktop apps, and chat through Slack and Telegram.
To get you started, here are 9 things to know about Inbox Zero, taken from its own pages and our grades.
- 1
Best for an open-source AI assistant for your inbox
Inbox Zero is an open-source AI assistant for Gmail and Outlook, with apps on every platform.
- 2
Paid plans start at $18 a month for each person
As its pricing page puts it: $18 per user / month, billed annually ($20 billed monthly).
- 3
You can try it first
7-day free trial on every plan; a credit card is required. Refunds are offered within 14 days of upgrading.
- 4
It runs on 5 platforms
Web, macOS, Windows, iOS and Android, with a browser extension too.
- 5
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.
- 6
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.
- 7
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.
- 8
A 2.0 GPA, above 2 of 51
That is against the other email apps we grade, on value, the free plan, features, ease of use and platforms.
- 9
Keep it
To replace Inbox Zero you would be making connections to other products, each kept working as those products change. That is not a weekend's work, with an AI app builder or without one.
Inbox Zero at a glance
- Pricing
- Free trial, from $18 per user / month, billed annually ($20 billed monthly)
- Free plan
- No
- Free trial
- 7-day free trial on every plan; a credit card is required. Refunds are offered within 14 days of upgrading.
- Runs on
- Web, macOS, Windows, iOS, Android, Browser extension
- Made by
- Inbox Zero Inc.
- Category
- Email Apps
- Our grade
- 2.0 GPA, fair
The report card
Best for an open-source AI assistant for your inbox
Inbox Zero is an open-source AI assistant for Gmail and Outlook, with apps on every platform. It labels your mail, drafts replies in your tone, blocks cold emails and unsubscribes you from newsletters, using rules you write in plain English. The hosted service has no free plan, the 7-day trial wants a card, Starter is $18 a user, a second account needs Plus at $28, and the phone apps leave some settings to the web.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | D | Starter 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 | D | No 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 | C | Mail 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 | C | No 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 | A | Web, 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. |
An A is worth 4 points, a B 3, a C 2, a D 1 and an F nothing. The GPA is the average of the five.
Who Inbox Zero is for
- 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
Who it is not for
- 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
Good to know
Good for
- 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
Worth knowing
- 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.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
$18
A month to start, for each person
Inbox Zero is a paid product with a free trial, starting at $18 per user / month, billed annually ($20 billed monthly).
The Tabs browser extension is free, and the code is open source if you'd rather host it yourself.
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.
Enterprise
Custom
SSO, SCIM, on-premise deployment and a dedicated account manager, arranged with the sales team.
Trying it first
7-day free trial on every plan; a credit card is required. Refunds are offered within 14 days of upgrading.
Read from getinboxzero.com on Oct 9, 2026.
Ways to pay less
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%.
Stated on getinboxzero.comEducation
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.
Stated on getinboxzero.comNonprofit
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.
Stated on getinboxzero.com
What the app costs elsewhere
Each country’s App Store price for “Inbox Zero Starter Monthly”, against $19.99 in the United States, in dollars at the day’s rate. The four cheapest and the four dearest of 11.
| Country | Price there | In dollars | Against the US |
|---|---|---|---|
| Canada | $24.99 | $17.57 | 12% less |
| Indonesia | Rp 349ribu | $19.52 | about the same |
| Turkey | ₺999,99 | $20.34 | about the same |
| Philippines | ₱ 1,290.00 | $20.53 | about the same |
| South Africa | R399.99 | $24.19 | 21% more |
| Germany | 22,99 € | $25.76 | 29% more |
| Brazil | R$ 129,90 | $25.95 | 30% more |
| United Kingdom | £19.99 | $26.43 | 32% more |
Part 03 · Features
What it does
Its main features, where it runs, what it works with and who makes it
6
Places it runs: Web, macOS, Windows, iOS, Android and Browser extension
Open source AI email assistant for Gmail and Outlook. Here is what it does, as its own site describes it, and what it covers: open source, self-hostable, AI features, chat assistant, email client, inbox filtering, workflow automation.
Its own gaps: Gmail and Outlook accounts only, and phone apps that send you to the web for settings.
- 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.
Where it runs
- Web
- macOS
- Windows
- iOS
- Android
- Browser extension
What it works with
- Gmail
- Outlook
- Slack
- Telegram
- Google Drive
- OneDrive
- Notion
- Stripe
Inbox Zero is made by Inbox Zero Inc.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
2/51
Other email apps it is graded above
Inbox Zero's GPA of 2.0 is higher than 2 of the 51 other email apps we grade, and level with 6.
It stands best on platforms and integrations (A, above 41 of 51) and worst on value for money (D, above 0).
Its paid plans start at $18 a month for each person, against a middle price of $4.99 for the category: 36 of the 45 others that charge start lower.
On features, ease of use and platforms it scores 2.7 out of 4. 9 tools score higher and cost less.
Each grade against the category
Every bar is all 52 email apps we grade, cut by the letter each got. Inbox Zero’s own letter is outlined.
- DValue for moneyAbove 0 of 51
- DFree plan and trialAbove 2 of 51
- CFeaturesAbove 0 of 51
- CEase of useAbove 0 of 51
- APlatforms and integrationsAbove 41 of 51
Price against what you get
Each dot is one of 50 email apps. Further left costs less; higher up scores better on features, ease of use and platforms. Inbox Zero is the marked dot.
What paid plans start at, a month (each step along is roughly double) →
Keep it, or make your own?
Whether this is something you could build for yourself with an AI app builder, and what you would give up.
Keep it
To replace Inbox Zero you would be making connections to other products, each kept working as those products change. That is not a weekend's work, with an AI app builder or without one.
That makes this kind of software worth paying for, not this one in particular: 43 of the 51 other email apps grade higher. It costs $216 a year. Inbox Zero is open source, so there is a third way: take its code and run it yourself.
What you could not
- Connections to other products, each kept working as those products change.
- An email client: sending, receiving, threading and searching years of mail.
- An AI model, which you can rent by the request but not make.
- Filters that read every message as it arrives.
- Apps for macOS, Windows, iOS and Android that stay in step with each other.
- It is priced for each person, which means accounts and billing for a team.
What this rests on. Inbox Zero’s listing: what it does, where it runs, what it plugs into and what it costs. It is a judgement about the kind of software this is. We have not built a replacement for it, and making your own means looking after it too. How we decide, and every tool’s verdict.
Part 05 · Alternatives
The alternatives
The tools it is most often weighed against, side by side
Fyxer, Jace AI, Cora, SaneBox and Superhuman Mail
The 5 tools Inbox Zero is most often weighed against, with where each one differs from it.
- 2.0GPA
Fyxer
Free plan · from $37/mo
AI assistant that sorts email, drafts replies and takes meeting notes.
- Fyxer has a free plan. Inbox Zero does not, though it has a free trial.
- Only Inbox Zero lists macOS, Windows, iOS and Android apps.
- Only Inbox Zero lists a browser extension.
- 2.0GPA
Jace AI
Free trial · from $20/mo
AI email agent with a web inbox for Gmail and Outlook.
- Only Inbox Zero lists macOS, Windows, iOS and Android apps.
- Only Inbox Zero lists a browser extension.
- Inbox Zero is open source and self-hostable, according to its own site.
- 1.8GPA
Cora
Free trial · from $20/mo
AI email assistant for Gmail that screens, drafts and briefs.
- Only Inbox Zero lists macOS, Windows, iOS and Android apps.
- Only Inbox Zero lists a browser extension.
- Inbox Zero is open source and self-hostable, according to its own site.
- 2.2GPA
SaneBox
Free trial · from $6.99/mo
AI email filtering that works inside the email app you already use.
- Only Inbox Zero lists macOS and Windows apps.
- Only Inbox Zero lists a browser extension.
- Inbox Zero is open source and self-hostable, according to its own site.
- 2.2GPA
Superhuman Mail
From $25/mo
Keyboard-driven email client for Gmail and Outlook with built-in AI.
- Inbox Zero is open source and self-hostable, according to its own site.
- Inbox Zero also covers chat assistant, inbox filtering and workflow automation.
- Superhuman Mail also covers calendar and booking links.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
13
Questions, each answered in a line or two
The short version of everything above, for when you only need the answer. Each one is told in full in its part of the guide.
Is Inbox Zero free?
No, Inbox Zero is a paid product, but you can try it first. 7-day free trial on every plan; a credit card is required.
How much does Inbox Zero cost?
Inbox Zero lists 4 plans. Starter: $18 per user / month, billed annually; $20 billed monthly.
What platforms does Inbox Zero work on?
Inbox Zero is available on Web, macOS, Windows, iOS and Android. It also has a browser extension.
Does Inbox Zero offer any discounts?
Inbox Zero publicly lists the following: Save up to 20% with annual billing; Student discount on request; Nonprofit and open-source project discounts.
Does Inbox Zero have a Linux app?
No Linux app was listed when its pages were read on Oct 9, 2026. Inbox Zero is listed for Web, macOS, Windows, iOS and Android.
Is Inbox Zero open source?
Yes. Inbox Zero is open source, according to its own site.
What does Inbox Zero integrate with?
Inbox Zero's listing names Gmail, Outlook, Slack, Telegram, Google Drive, OneDrive, Notion and Stripe.
Does Inbox Zero have a student discount?
Student discount on request. The pricing FAQ says students can email the company to have a discounted plan set up.
Who makes Inbox Zero?
Inbox Zero is made by Inbox Zero Inc.
What are the alternatives to Inbox Zero?
The closest alternatives to Inbox Zero in our directory are Fyxer, Jace AI, Cora, SaneBox and Superhuman Mail.
How does Inbox Zero compare with other email apps?
Inbox Zero's GPA of 2.0 is higher than 2 of the 51 other email apps we grade, and level with 6.
Is Inbox Zero good value for money?
ToolGPA grades Inbox Zero D for value for money. Its paid plans start at $18 a month for each person, against a middle price of $4.99 for the category: 36 of the 45 others that charge start lower.
Could I make my own version of Inbox Zero?
To replace Inbox Zero you would be making connections to other products, each kept working as those products change.
Where this guide comes from
The prices, plans, platforms and features were read from Inbox Zero’s own pages on Oct 9, 2026, and the grades were given on Oct 10, 2026. Graded from this listing, whose facts were read from Inbox Zero's own pages on 9 October 2026. Also tested with a demo account on 2026-04-19.
Every tool we list gets five grades, A to F, each with its reason, and a GPA that averages them. How each is decided is at toolgpa.com/grades. This guide is ToolGPA’s own work; it is not made, paid for or approved by Inbox Zero Inc. Prices change, so check getinboxzero.com before you buy.
- getinboxzero.com/
- getinboxzero.com/pricing
- getinboxzero.com/desktop
- getinboxzero.com/email-client
- getinboxzero.com/about
- getinboxzero.com/terms
- docs.getinboxzero.com/introduction
- docs.getinboxzero.com/essentials/mobile-apps
- docs.getinboxzero.com/essentials/inbox-zero-tabs-extension
- docs.getinboxzero.com/hosting/quick-start
- raw.githubusercontent.com/elie222/inbox-zero/main/README.md
Part 07 · About
About ToolGPA
Who made this guide, what else is on the site, and how to cite it
3,189
Tools graded, in 94 categories
ToolGPA grades software the way a school report grades a pupil: five subjects, a letter for each with the reason written beside it, and a GPA that averages them. Prices, plans and platforms are read from each maker’s own pages and dated, so you always know how fresh a figure is.
Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Every tool on the site has a guide like this one, free to download and pass on. It all lives at toolgpa.com.
3,189
tools graded
94
categories
426
price changes on record
579
apps priced in 12 countries
What else is on toolgpa.com
- Inbox Zero, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/inbox-zero
- How grades are givenThe rules behind every letter and every GPAtoolgpa.com/grades
- Value chartsWhat each tool costs against what it scores, for every categorytoolgpa.com/charts
- CompareAny two tools side by side, plan by plantoolgpa.com/compare
- Price changesEvery price rise and cut on record, each with its sourcetoolgpa.com/price-changes
- Prices by countryWhat apps cost on the App Store in 12 countriestoolgpa.com/prices-by-country
- Pay lessEvery public discount: yearly billing, students, nonprofitstoolgpa.com/save
- Keep or makeWhich tools are worth paying for, and which you could build yourselftoolgpa.com/keep-or-make
Scan for the live page
Prices and grades as they are today
Quoting this guide?
Please name ToolGPA and link to the live page, so readers can check the figures for themselves:
ToolGPA, "Inbox Zero: The Insider's Guide", checked Oct 9, 2026. https://toolgpa.com/tools/inbox-zero
Know someone choosing between email apps?
Send them this guide: toolgpa.com/tools/inbox-zero/guide
ToolGPA elsewhere: youtube.com/@toolgpa
See our other guides
The best-graded email apps after Inbox Zero, each with an Insider's Guide of its own.
- Email Apps Insider's GuideEvery one of the 52 email apps we grade, compared
- Microsoft Outlook Insider's GuideMicrosoft's email and calendar app for desktop, mobile and web3.6 GPA
- BlueMail Insider's GuideCross-platform email client with a unified inbox and built-in AI3.2 GPA
- Thunderbird Insider's GuideFree, open-source email app for Windows, macOS, Linux and Android3.2 GPA
Choosing software? Every tool graded, every price dated.
Compare tools at toolgpa.com ›Everything in this guide is ToolGPA’s own summary of what Inbox Zero’s pages, its app-store listings and public reviews said on the dates shown. Grades are our judgement under the rules at toolgpa.com/grades. Every grade, review and ranking on ToolGPA is our own judgement. No company can pay for a grade or change one. Inbox Zero is a trademark of its owner, and this guide is not made, paid for or approved by Inbox Zero Inc. Prices and plans change: check getinboxzero.com before you buy.