If you’ve ever tried to send someone a calendar event and ended up in a confusing back-and-forth of “what time zone are you in?” and “can you just email me the details?”, you are not alone. Sharing calendar events across different apps and devices is one of those things that should be simple but somehow never quite is.
The good news? There’s a free tool that takes all the hassle out of it. In this post I’m going to show you exactly how to generate ICS files and calendar links for free, using a tool called CalTools.
Contents
What even is an ICS file?
Before we get into the how, let’s cover the what. An ICS file (short for iCalendar, with the .ics extension) is the universal standard format for calendar events. It’s supported by every major calendar app you can think of.
When someone opens an ICS file, their calendar app reads the event details (title, date, time, timezone, location, description) and asks if they want to add it. It’s the most reliable way to share a calendar event regardless of what apps or devices either of you are using.
You can attach an ICS file to an email, drop it into a Slack message, or host it on a website for one-click importing.
What about calendar links?
A calendar link is slightly different. Rather than a file someone downloads and opens, a calendar link takes them directly to a specific app in their browser – like Google Calendar – with all the event details already pre-filled.
Use a calendar link when you know your audience and want a smooth, frictionless experience for a specific platform. Adding an “Add to Google Calendar” button to a landing page? Calendar link, every time.
Use an ICS file when you’re dealing with a mixed audience, attaching to an email, or you want something that’ll work universally, whatever app someone happens to use.
Why do I actually need this?
More often than you’d think. Here are the kinds of situations this genuinely comes up in:
You’re running a webinar or online event. You want attendees to save the date. You could just write the time in an email and hope for the best, or you could give them a one-click calendar link or ICS file and actually have them show up.
You’re a freelancer or consultant. You need to send a client a meeting time. They use Outlook; you use Google Calendar. An ICS file works for both without anyone needing to screenshot anything or copy-paste times manually.
You run a community group, club, or regular event. Pop an ICS link or calendar button on your website or in a group chat. Members save the event without signing up for anything or needing to be added to a calendar.
You’re building a website or landing page. Calendar links are just URLs – you can drop them into a button with no backend required.
How to generate an ICS file with CalTools
Right, let’s actually do this. Head over to caltools.app – no account needed, no email required.
Step 1: Fill in your event details
You’ll see a simple form with the following fields:
- Event Title — the name of your event as it’ll appear in the calendar app
- All-day event toggle — useful for holidays, birthdays, or deadlines with no specific time
- Start date and time
- End date and time — leave this blank and it’ll default to one hour after the start
- Timezone — this defaults to your local timezone automatically, which is handy
- Location — a physical address, room name, or a meeting link (Zoom, Teams, Google Meet, etc.)
- Description — any extra notes, an agenda, dial-in numbers, or instructions for attendees
The preview panel on the right updates live as you type, so you can see exactly what your event will look like before you generate anything.
Step 2: Download your ICS file or copy a calendar link
Once you’ve filled in your event details, you’ll see two options:
Download .ics File – click this to get a .ics file you can attach to an email or message, or host on your website.
Add to Calendar links – underneath the download button, you’ll find direct calendar links for:
- Google Calendar
- Outlook.com
- Microsoft 365
- Yahoo Calendar
Each link has a Copy button, a Share option, and an Embed option if you want to drop an “Add to Calendar” button straight into your website HTML.
For Apple Calendar and Outlook desktop, use the .ics download. These apps don’t support web links in the same way that browser-based calendars do, but they fully support ICS files. Double-click the downloaded file and it opens straight in your default calendar app.
That’s it. Send the ICS file as an email attachment, copy a calendar link into your newsletter, or paste the embed code into your website. Recipients click or open the file and the event lands straight in their own calendar with the correct timezone and everything.
Will the timezone be correct for people in other countries?
Yes. This is one of the things CalTools handles really well. It embeds the IANA timezone you select (for example, Europe/London) directly into the ICS file. When someone in New York opens it, their calendar app automatically converts the event to their local time. The same applies to calendar links.
Can I convert an existing ICS file?
Yes — there’s a Convert Existing tab on the CalTools homepage. Drop in an .ics file from Google Calendar, Outlook, Apple Calendar, or anywhere else, and it’ll read the event details for you. From there you can generate new links or a fresh .ics file to share onwards.
Is it really free?
Yes. Creating a single ICS file or calendar link is always free. There’s no account, no email address, and no payment required. A Pro plan for bulk generation is coming soon for power users who need to create lots of events at once, but for most everyday use cases, the free version does everything you need.
Everything also runs entirely in your browser, no event data is sent to a server or stored anywhere. Which is a nice bonus if you’re privacy-conscious.
A quick summary
| What you need | What to use |
|---|---|
| Sharing with a mixed audience (email, Slack, etc.) | ICS file download |
| Adding a “save the date” button to a website | Calendar link with embed |
| Sending a client a meeting time | ICS file attached to an email |
| “Add to Google Calendar” button on a landing page | Google Calendar link |
| Works with Apple Calendar and Outlook desktop | ICS file download |
If you regularly share events with clients, an audience, or a community, having a reliable way to generate ICS files and calendar links is one of those small things that makes a big difference to how professional and organised you come across.
Give CalTools a go – it takes about 30 seconds to generate your first calendar file, and it’s completely free.
Found this useful? Share it with someone who’s still copy-pasting event times into emails.
