The Calendar 366 Insider’s Guide
Everything we know about Calendar 366 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.
Calendar 366
The Insider’s Guide
Calendar and task app for iPhone, iPad, Apple Watch and Mac
Every plan, grade, refund rule and rival among calendar and scheduling apps, read from Calendar 366’s own pages.
Made by Vincent Miethe · 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 Calendar 366’s own pages, its app-store listings and our grades. Every fact in it is on Calendar 366’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
2.6
GPA, above 30 of the 74 other calendar and scheduling apps we grade
Calendar 366 is a calendar and task app for Apple devices made by Vincent Miethe, a developer in Berlin. It shows events and tasks from iCloud, Google, Outlook, Microsoft 365, Todoist, Fastmail and CalDAV accounts in one place, takes typed natural-language entries, and adds a menu bar calendar on the Mac. The app is a free download with basic features, and a Pro subscription or one-time purchase unlocks the rest.
To get you started, here are 9 things to know about Calendar 366, taken from its own pages and our grades.
- 1
Best for events and tasks together on Apple devices
It's Apple only, Siri AI is still a beta, and the MCP link to AI assistants is Mac only.
- 2
Paid plans start at $1.67 a month when paid by the year
As its pricing page puts it: $19.99 per year for Pro on the App Store.
- 3
There is a free plan
Free download with basic features. The site does not list which features are premium; all of them can be tried for 7 days before choosing a subscription or a one-time purchase.
- 4
It runs on 2 platforms
iOS and macOS.
- 5
Natural language entry
Type what, when and where to create an event or task, with shorthand such as /Work for a calendar, -r1w for a weekly repeat and ! for priority. Apple Intelligence can be picked as the engine on iOS, iPadOS or macOS 27.
- 6
Tasks next to events
Tasks sit in the calendar with reminders, location-based alerts, priorities and notes, and can be filtered by today, overdue or important. They sync with Apple Reminders, Google Tasks, Microsoft to-dos and Todoist.
- 7
Views and calendar sets
Year, month, week, day and agenda views, plus month and week views paired with a list, in portrait and landscape. Calendar sets group calendars and lists and sync across devices.
- 8
A 2.6 GPA, above 30 of 74
That is against the other calendar and scheduling apps we grade, on value, the free plan, features, ease of use and platforms.
- 9
Keep it
The plain part of Calendar 366 you could make: calendar, tasks and natural-language input. What surrounds it you could not. The 6 things listed below take a company, not a weekend.
Calendar 366 at a glance
- Pricing
- Free plan, from $19.99 per year for Pro on the App Store
- Free plan
- Yes
- Free trial
- 7-day trial of all premium features
- Runs on
- macOS, iOS
- Made by
- Vincent Miethe
- Category
- Calendar & Scheduling
- Our grade
- 2.6 GPA, good
The report card
Best for events and tasks together on Apple devices
Calendar 366 shows events and tasks together on iPhone, iPad, Apple Watch and Mac, takes typed entries, and Pro is $19.99 a year. Neither the site nor the App Store says which features stay free after the 7-day trial, and several App Store prices carry no billing period. It's Apple only, Siri AI is still a beta, and the MCP link to AI assistants is Mac only.
| Subject | Grade | Comment |
|---|---|---|
| Value for money | A | Pro is $19.99 a year, which is $1.67 a month against a $6 middle for calendars, and Pro Family is $29.99 a year, near the bottom of this category for a paid app. The App Store list also shows items at $19.99 and $49.99 with no billing period at all. |
| Free plan and trial | C | There is a free download, and every premium feature is open for 7 days. The problem is that neither the site nor the App Store listing says which features stay free afterwards, so the only way to learn where the wall is, is to walk into it. |
| Features | B | Events and tasks together: typed entry with shorthand like /Work and -r1w, tasks synced to Reminders, Google Tasks and Todoist, calendar sets, an invitation inbox, 20 widgets, 10 watch complications and a Mac menu bar calendar. The MCP link to Claude Desktop is Mac only, and Siri AI is still beta. |
| Ease of use | C | No rating on record. You can type an event in plain words, but the shorthand that makes it quick, /Work, -r1w, an exclamation mark for priority, is a small language to learn, and there are accounts to connect before any of it. |
| Platforms and integrations | C | One family of devices: iPhone, iPad, Apple Watch and Mac, with no Android, Windows or web version listed. Inside Apple it connects to iCloud, Google, Outlook, Microsoft 365, Fastmail, CalDAV, Shortcuts and Claude Desktop over MCP. |
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 Calendar 366 is for
- Fits if everything you own is Apple and you want events and tasks in one app
- Works for people with a mix of iCloud, Google, Microsoft 365, Fastmail and Todoist accounts
Who it is not for
- Skip it if you use Android, Windows or a web browser, as it's Apple devices only
- Not for you if you want to know what's free before you start, because the maker doesn't publish it
- Watch out: App Store items at $19.99, $49.99, $29.99 and $69.99 show no billing period, and single-user Pro has no monthly price
- Tight if you wanted Siri AI today, which is in beta, English only and needs iOS or macOS 27
- Not for you if you want the AI assistant link on iPhone, as the MCP connection is Mac only
Good to know
Good for
- People who keep everything on Apple devices and want events and tasks in one app
- Mixing iCloud, Google, Microsoft 365, Fastmail and CalDAV accounts
- Buyers who prefer a one-time purchase to a subscription
- Mac users who want to manage their calendar from an AI assistant over MCP
Worth knowing
- Apple only: iPhone, iPad, Apple Watch and Mac. No Android, Windows or web version is listed.
- After the 7-day trial the free download keeps only basic features, and the vendor does not publish which features are premium.
- Prices appear only as App Store in-app purchases. Several have no billing period, and no monthly price for single-user Pro is shown.
- Siri AI is in beta, English only, and needs iOS, iPadOS or macOS 27. The MCP connection to AI assistants is Mac only.
Part 02 · Pricing
What it costs
Every plan, the free plan, ways to pay less and how prices have moved
$1.67
A month to start, paid by the year. There is a free plan too
Calendar 366 has a free plan. Paid plans start at $19.99 per year for Pro on the App Store.
Free
$0
Free download with basic features. Neither the site nor the App Store listing says which features stay free after the 7-day trial.
Pro (Yearly)
$19.99
per year
Yearly subscription that unlocks the premium features, as labelled in the App Store's in-app purchase list.
Pro (iOS)
$19.99
billing basis not shown on the App Store listing
Listed without a period. The vendor's FAQ says a one-time purchase is offered next to the subscriptions.
Pro
$49.99
billing basis not shown on the App Store listing
Listed without a period or platform label. The site describes the app as a universal purchase across iPhone, iPad, Apple Watch and Mac.
Pro Family (Monthly)
$4.99
per month, or $29.99 per year as Pro Family (Yearly)
Family version of the Pro subscription, with monthly and yearly options in the App Store's in-app purchase list.
Pro Family (iOS)
$29.99
billing basis not shown on the App Store listing
Family version listed without a period. A second item named Pro Family, with no platform label, is listed at $69.99.
The free plan
Free download with basic features. The site does not list which features are premium; all of them can be tried for 7 days before choosing a subscription or a one-time purchase.
Trying it first
7-day trial of all premium features
Read from apps.apple.com on Oct 9, 2026.
Ways to pay less
Lifetime license
One-time purchase in place of a subscription
The FAQ on Calendar 366's site says that after the 7-day trial you can choose a subscription or a one-time purchase. The App Store lists Pro (iOS) at $19.99 and Pro at $49.99 without a billing period.
Stated on calendar366.com
What the app costs elsewhere
Each country’s App Store price for “Calendar 366 Pro (Yearly)”, 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 |
|---|---|---|---|
| Indonesia | Rp 99ribu | $5.54 | 72% less |
| Turkey | ₺299,99 | $6.10 | 69% less |
| India | ₹ 599 | $6.19 | 69% less |
| Philippines | ₱ 399.00 | $6.35 | 68% less |
| Canada | $24.99 | $17.57 | 12% less |
| Australia | $29.99 | $20.94 | about the same |
| Germany | 19,99 € | $22.40 | 12% more |
| United Kingdom | £17.99 | $23.78 | 19% more |
Part 03 · Features
What it does
Its main features, where it runs, what it works with and who makes it
2
Places it runs: macOS and iOS
Calendar and task app for iPhone, iPad, Apple Watch and Mac. Here is what it does, as its own site describes it, and what it covers: one-time purchase, AI features, tasks, natural-language input, calendar, menu bar app.
The MCP link to Claude Desktop is Mac only, and Siri AI is still beta.
- Natural language entry
- Type what, when and where to create an event or task, with shorthand such as /Work for a calendar, -r1w for a weekly repeat and ! for priority. Apple Intelligence can be picked as the engine on iOS, iPadOS or macOS 27.
- Tasks next to events
- Tasks sit in the calendar with reminders, location-based alerts, priorities and notes, and can be filtered by today, overdue or important. They sync with Apple Reminders, Google Tasks, Microsoft to-dos and Todoist.
- Views and calendar sets
- Year, month, week, day and agenda views, plus month and week views paired with a list, in portrait and landscape. Calendar sets group calendars and lists and sync across devices.
- Meetings and invitations
- Creates Zoom, Google Meet and Microsoft Teams meetings and opens join links for services such as Webex and FaceTime. Invitations arrive in an inbox and can be accepted or declined there.
- Widgets, Apple Watch and menu bar
- 20 home screen and desktop widgets, 6 lock screen widgets and 10 watch complications. The Watch app creates events and completes tasks, and the Mac version adds a full menu bar calendar.
- Shortcuts, URL scheme and MCP
- Supports Apple Shortcuts and a cal366:// URL scheme for automation. On Mac it can connect to Claude Desktop or LM Studio through the Model Context Protocol to show, create and reschedule entries by chat.
Where it runs
- macOS
- iOS
What it works with
- iCloud
- Google Calendar
- Outlook
- Microsoft 365
- Todoist
- Zoom
- Fastmail
- Claude Desktop
Calendar 366 is made by Vincent Miethe.
Part 04 · Standing
Where it stands
Its grades against its category, and whether to keep it or make your own
30/74
Other calendar and scheduling apps it is graded above
Calendar 366's GPA of 2.6 is higher than 30 of the 74 other calendar and scheduling apps we grade, and level with 13.
It stands best on value for money (A, above 45 of 74) and worst on ease of use (C, above 0).
Its paid plans start at $1.67 a month when paid by the year, against a middle price of $6 for the category: 4 of the 52 others that charge start lower.
On features, ease of use and platforms it scores 2.3 out of 4. 7 tools score higher and cost less.
Each grade against the category
Every bar is all 75 calendar and scheduling apps we grade, cut by the letter each got. Calendar 366’s own letter is outlined.
- AValue for moneyAbove 45 of 74
- CFree plan and trialAbove 3 of 74
- BFeaturesAbove 47 of 74
- CEase of useAbove 0 of 74
- CPlatforms and integrationsAbove 10 of 74
Price against what you get
Each dot is one of 67 calendar and scheduling apps. Further left costs less; higher up scores better on features, ease of use and platforms. Calendar 366 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
The plain part of Calendar 366 you could make: calendar, tasks and natural-language input. What surrounds it you could not. The 6 things listed below take a company, not a weekend.
It costs $19.99 a year.
What you could make
- Calendar, tasks and natural-language input: an app builder makes these well.
What you could not
- A native app living in the menu bar.
- Apps for macOS and iOS that stay in step with each other.
- It plugs into other products, iCloud, Google Calendar and Outlook among them.
- AI features, unless you pay a model provider for each request yourself.
- Hooks into the device itself: an Apple Watch app, widgets, Shortcuts and the lock screen.
- The depth: we grade its features B, which means it covers the whole job.
What this rests on. Calendar 366’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
Fantastical, BusyCal, Calendars by Readdle, Apple Calendar and Dato
The 5 tools Calendar 366 is most often weighed against, with where each one differs from it.
- 2.4GPA
Fantastical
Free plan · from $4.75/mo
Calendar and tasks app for Apple devices, Windows and Googlebook.
- Only Fantastical lists a Windows app.
- Calendar 366 can be bought with a one-time purchase.
- Calendar 366 also covers menu bar app.
- 2.4GPA
BusyCal
Free plan · from $49.99 one-time
- 3.0GPA
Calendars by Readdle
Free plan · from $19.99/yr
Calendar and task planner for iPhone, iPad, Mac and Apple Watch.
- Calendar 366 can be bought with a one-time purchase.
- Calendar 366 also covers menu bar app.
- Calendars by Readdle also covers habit tracking.
- 3.2GPA
Apple Calendar
Free
Free built-in calendar for iPhone, iPad, Mac and iCloud.com.
- Only Apple Calendar lists a web app.
- Calendar 366 can be bought with a one-time purchase.
- Calendar 366 also covers menu bar app.
- 2.4GPA
Dato
Free trial · from $18 one-time
Mac menu bar calendar with world clocks and meeting alerts.
- Calendar 366 has a free plan. Dato does not, though it has a free trial.
- Only Calendar 366 lists an iOS app.
- Calendar 366 also covers tasks and natural-language input.
Part 06 · Questions
Quick answers
The questions people ask about it, each answered in a line or two
14
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 Calendar 366 free?
Calendar 366 has a free plan. Free download with basic features.
How much does Calendar 366 cost?
Calendar 366 lists 6 plans. Free: $0.
What platforms does Calendar 366 work on?
Calendar 366 is available on iOS and macOS.
Does Calendar 366 offer any discounts?
Calendar 366 publicly lists the following: One-time purchase in place of a subscription.
Does Calendar 366 have an Android app?
No Android app was listed when its pages were read on Oct 9, 2026. Calendar 366 is listed for iOS and macOS.
Does Calendar 366 have a Windows app?
No Windows app was listed when its pages were read on Oct 9, 2026. Calendar 366 is listed for iOS and macOS.
Is Calendar 366 open source?
Calendar 366 is not described as open source on its own site, as read on Oct 9, 2026.
What does Calendar 366 integrate with?
Calendar 366's listing names iCloud, Google Calendar, Outlook, Microsoft 365, Todoist, Zoom, Fastmail and Claude Desktop.
Does Calendar 366 have a free trial?
Yes. 7-day trial of all premium features.
Who makes Calendar 366?
Calendar 366 is made by Vincent Miethe.
What are the alternatives to Calendar 366?
The closest alternatives to Calendar 366 in our directory are Fantastical, BusyCal, Calendars by Readdle, Apple Calendar and Dato.
How does Calendar 366 compare with other calendar and scheduling apps?
Calendar 366's GPA of 2.6 is higher than 30 of the 74 other calendar and scheduling apps we grade, and level with 13.
Is Calendar 366 good value for money?
ToolGPA grades Calendar 366 A for value for money. Its paid plans start at $1.67 a month when paid by the year, against a middle price of $6 for the category: 4 of the 52 others that charge start lower.
Could I make my own version of Calendar 366?
The plain part of Calendar 366 you could make: calendar, tasks and natural-language input.
Where this guide comes from
The prices, plans, platforms and features were read from Calendar 366’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 Calendar 366's own pages on 9 October 2026. Also tested with a demo account on 2026-04-10.
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 Vincent Miethe. Prices change, so check calendar366.com before you buy.
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
- Calendar 366, kept up to dateEverything in this guide, with prices and grades as they are todaytoolgpa.com/tools/calendar-366
- 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, "Calendar 366: The Insider's Guide", checked Oct 9, 2026. https://toolgpa.com/tools/calendar-366
Know someone choosing between calendar and scheduling apps?
Send them this guide: toolgpa.com/tools/calendar-366/guide
ToolGPA elsewhere: youtube.com/@toolgpa
See our other guides
The best-graded calendar and scheduling apps after Calendar 366, each with an Insider's Guide of its own.
- Calendar & Scheduling Insider's GuideEvery one of the 75 calendar and scheduling apps we grade, compared
- Notion Calendar Insider's GuideFree calendar app that connects to Notion databases3.6 GPA
- Google Calendar Insider's GuideOnline calendar from Google, free with a personal account3.4 GPA
- World Time Buddy Insider's GuideVisual time zone converter and world clock for planning calls3.4 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 Calendar 366’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. Calendar 366 is a trademark of its owner, and this guide is not made, paid for or approved by Vincent Miethe. Prices and plans change: check calendar366.com before you buy.