How to sync iCloud with Google Calendar (step by step, no duplicates)

Updated August 2026 · the Calen1 team

Your personal life lives on your iPhone: the dentist appointment, your mum's birthday, Friday's flight. You capture all of it with Siri or from the Calendar app, so it ends up in iCloud. But your work happens in Google Calendar, and nobody there can see any of it. You know how that ends: someone books a meeting on top of your flight, you accept it on autopilot, and on Thursday you find the clash.

The frustrating part is that the obvious fix doesn't work. You publish your iCloud calendar, paste the link into Google, and it looks like it worked — the events show up. Then you move an appointment on your iPhone and Google keeps showing the old time for hours. Or worse: you export an .ics file, import it, and months later every event exists twice with no way to tell which one is real.

This guide explains why Apple and Google don't understand each other on their own, what the real options are, and how Apple's app-specific password works — the part everyone finds suspicious, and the part that's actually protecting you. How Calen1 solves it comes at the end, but the first steps are useful even if you never pay for it.

Why iCloud and Google Calendar don't talk to each other

It isn't an oversight: they're two worlds that were never designed to work together. Apple exposes your calendars through a protocol called CalDAV, an open and rather old standard. Google Calendar runs on its own API. Neither of them offers a "connect me to the other one" button.

The only thing Apple gives you out of the box is publishing a calendar as an ICS link, and Google will happily subscribe to that kind of link. It sounds perfect, but it has three problems that make it useless for a calendar you use every day:

• It's read-only. You can see your iCloud events in Google, but you can't edit them there, and nothing you do in Google goes back to the iPhone.
• It doesn't update quickly. Google checks those external links whenever it feels like it, and that can take hours. If you move an appointment in the morning, your colleagues may still be seeing the old time all afternoon.
• The link is your entire calendar. Anyone holding that URL sees your events, titles and all, without asking you.

And the .ics file shortcut is worse still: it's a photograph of a moment. You import it once, it never updates, and if you import it again to "refresh" it, you end up with everything duplicated.

The three ways to connect them (and which one actually works)

Before paying for anything, it helps to see the full menu:

1. Subscribing by public link (ICS). Free and done in five minutes. Useful if all you want is to glance at your personal events from your work computer and you don't mind the lag. Useless for coordinating anything in time.
2. Exporting and importing .ics. Only makes sense for a one-time move: you're switching platforms, you carry your history across, and you're done. As a sync method, it's a duplicate factory.
3. A bridge that speaks both languages. A service that connects to iCloud over CalDAV and to Google through its API, watches for changes on both sides and mirrors them. It's the only option that stays current and the only one that can be bidirectional.

Calen1 is the third kind: it connects Google Calendar, Microsoft 365 and iCloud to each other, checks for changes roughly every two minutes and mirrors whatever was created, edited or deleted. It isn't instant and there's no point pretending otherwise: count on a couple of minutes, not seconds.

Apple's app-specific password, demystified

This is where most people stop. When you connect iCloud to any outside service, you'll be asked for your iCloud email and an app-specific password. It is not your Apple password, and that distinction is the whole security story.

What it is. A 16-character key Apple generates for one single app, in the format xxxx-xxxx-xxxx-xxxx. It gives that app access to your iCloud data, but it can't be used to sign in to your Apple Account, change your details or buy anything. It's a key to one door, not the whole keyring.

Why it exists. Apple requires two-factor authentication. An outside app can't type the six-digit code that arrives on your iPhone, so Apple solved the problem the other way around: instead of handing your real password to a third party, you hand over a disposable key that you can cancel whenever you like, without touching anything else in your account.

How to generate one:

1. Go to account.apple.com in any browser and sign in with your Apple Account.
2. Open the Sign-In and Security section.
3. Choose App-Specific Passwords and generate a new one.
4. Give it a name you'll recognise later, for example "Calen1".
5. Copy the key that appears. It's only shown once: if you close the window, it's gone and you have to generate another.
6. Paste it into the service along with your iCloud email.

Two useful warnings. If you don't have two-factor authentication turned on, the option simply won't appear in your account — turn it on first. And if you ever change your Apple Account password, every app-specific password is cancelled at once and has to be regenerated, so if the sync one day stops working for no apparent reason, start there.

To revoke it, go back to the same screen and delete it. Access is cut off at that moment. Calen1 never asks for or stores your normal Apple password, and the credentials it does store are encrypted.

One way or both ways: which suits you

With iCloud you can pick the direction of the sync with a button, and the decision matters more than it looks.

One way (iCloud to Google). Your personal events appear in Google, and nothing that happens in Google touches your iPhone. It's the calm option: there's no way for a change at work to move or delete a personal appointment. Pick it if all you want is for the office to see that you're busy, and nothing more.

Both ways. Changes travel in both directions: what you edit or create on the Google side inside the synced calendar comes down to iCloud and shows up on your iPhone. That's what you want if you work from your computer and expect your phone to stay current without retyping anything. Be clear about what "both ways" really means, though: if you delete the copy from Google, the original event in iCloud goes too.

Recommendation: start one way for the first week. Once you've seen how it behaves and you trust what you're looking at, switch it to both ways. It's a button, not a permanent decision.

The "iCloud (Calen1)" calendar and why nothing gets mixed up

The legitimate fear when connecting two calendars is ending up with a soup where you can't tell which event is yours, which is a copy and which is surplus. That's why events arriving from iCloud don't get mixed in with yours: they land in a new, dedicated calendar called "iCloud (Calen1)" inside your Google account.

That gives you three things for free. You can give it its own colour to recognise at a glance what's personal. You can hide it with one click when you're sharing your screen in a meeting. And if you ever disconnect the account, you know exactly what goes and what stays, because your work events were never in there.

The other classic problem is duplicates. Calen1 marks every copy it creates internally and records which event on the other side it corresponds to. That's why a copy doesn't bounce back and get copied again in a loop. And when you connect for the first time, instead of dumping everything on top, it reconciles: it looks at the events that already existed on both sides and pairs them up.

Details that tend to break in other tools and are covered here: a recurring series is mirrored as a single series, not as dozens of loose events; all-day events are respected as such; and time zones are preserved, so a flight entered in Mexico City doesn't shift on its own.

And if you'd rather your colleagues didn't read your personal business, there's privacy mode: the event blocks the slot showing only as "Busy", with no title or description. They see you're unavailable; they don't see which doctor you're going to.

Step by step: getting iCloud and Google in sync

1. Generate the app-specific password at account.apple.com as described above and keep it handy.
2. Create your Calen1 account. No passwords: you get in with a sign-in link sent to your email, or with "Continue with Google".
3. Connect your Google account and authorise calendar access.
4. Connect iCloud with your iCloud email and the app-specific password. If it's rejected, check that you pasted it in full, with hyphens and no trailing spaces.
5. Choose the direction: one way or both ways.
6. Decide whether to turn on privacy mode so personal events show only as "Busy".
7. Wait a couple of minutes and open Google Calendar. The "iCloud (Calen1)" calendar should be there with your events.

The first pass can take a little longer than usual because it's reconciling your history. After that, it settles into the roughly-every-two-minutes rhythm. Good moment to give the new calendar a colour.

Honest limits, security and price

So there are no surprises, here's what Calen1 doesn't do today:

• It isn't instant. The cycle runs roughly every two minutes.
• There's no mobile app, it's a web tool. In practice that matters little: your events live in Google and in iCloud, so you see them in the normal apps on your iPhone and your computer.
• It only syncs calendar events. No tasks, contacts or email.
• It doesn't support Yahoo, Fastmail or Nextcloud. Today it's Google Calendar, Microsoft 365 and iCloud.
• There are no team features, no roles, and no Slack, Teams, Zoom or Notion integration.
• There's no free plan and no automatic free trial.

About your data: credentials are stored encrypted, they aren't sold, and they aren't used for advertising or to train artificial intelligence models, in line with Google's Limited Use policy. You can disconnect any account or delete yours whenever you want.

Prices are per user, in Mexican pesos: the Base plan costs $50 a month or $500 a year, and includes syncing Google, Microsoft 365 and iCloud, privacy mode and multiple connected accounts. The Pro plan costs $149 a month or $1,490 a year, and adds Agenda Pro: your own booking page, which only offers slots that are free across all your calendars at once, with your logo and your colour, and which shows guests the times in their own time zone. Paying yearly works out to ten months, so two are free.

If all you need is to stop having meetings booked on top of your personal life, the Base plan and one afternoon of setup will do it.