To convert VCF contact birthdays to an ICS calendar file, use Univik ICS Converter load the VCF file, select ICS as the output and export. The converter extracts the BDAY field from every contact that has one and creates a recurring annual calendar event for each birthday. Only contacts with a BDAY field in the VCF produce calendar events contacts with no birthday data are skipped. The resulting ICS file imports into Google Calendar, Apple Calendar, Outlook and any other calendar app that accepts the ICS format.
What the Conversion Actually Does
A VCF file stores contact information. An ICS file stores calendar events. They are different data types and the conversion is not a simple format change it is an extraction process.
When you convert VCF to ICS for birthday reminders, the converter reads every contact in the VCF file, looks for the BDAY field in each contact entry and creates one annual recurring calendar event per birthday found. Contacts without a BDAY field produce no calendar events they are simply skipped.
The output is an ICS file containing one VEVENT component per birthday, each set to recur annually. Import this ICS file into any calendar application and you get a birthday calendar a separate calendar layer showing upcoming birthdays from your contact list.
The BDAY Field: Where Birthday Data Lives in VCF
In a VCF file, birthday data is stored in the BDAY property. In a well-structured vCard 3.0 entry it looks like this:
VERSION:3.0
FN:Sarah Johnson
TEL;TYPE=CELL:+447911123456
EMAIL:sarah@example.com
BDAY:1985-06-15
END:VCARD
The BDAY value is a date in ISO 8601 format: YYYY-MM-DD. This is the full-date format year, month and day all present. When a converter reads this, it creates a calendar event on June 15th that recurs annually and can calculate the person’s age each year because the birth year (1985) is known.
The BDAY Format Problem
The BDAY field is one of the most inconsistently formatted fields across VCF sources. Different platforms store it differently and these differences affect how well the conversion to ICS works.
| BDAY Format | Example | Source | ICS Conversion Result |
|---|---|---|---|
| Full date (vCard 3.0) | BDAY:1985-06-15 |
iPhone, Google Contacts | Works perfectly. Annual event with age calculation. |
| Full date (vCard 2.1) | BDAY:19850615 |
Android, older Outlook | Works. Converter parses the compact format to the same result. |
| Month-day only | BDAY:--0615 |
iPhone (when year not set) | Works but no age shown. Only day and month matter for the annual reminder. |
| Year-month only | BDAY:1985-06 |
Rare some legacy apps | May create an event on the 1st of the month. Day is unknown. |
| Text format | BDAY:June 15, 1985 |
Non-standard exporters | May fail depends on converter’s parsing capability. |
| Missing | No BDAY line | Any platform many contacts have no birthday set | Contact skipped. No calendar event created. |
iPhone exports use month-day-only format when no year is set
When you add a birthday to an iPhone contact without entering the year, iPhone stores it as BDAY:–MMDD (for example BDAY:–0615 for June 15th with no year). This is valid vCard 4.0 syntax. Most converters handle it correctly and create a recurring annual event on that date they just cannot show the person’s age because the birth year is unknown. If you want age display in your birthday calendar, edit the contact on iPhone to add the birth year.
Check Which Contacts Have Birthday Data
Before converting, it is worth knowing how many contacts in your VCF actually have birthday data. Most contact lists have sparse birthday coverage people tend to add birthdays selectively rather than for every contact.
The quickest check: open the VCF file in a text editor (Notepad on Windows) and use Find (Ctrl+F) to search for BDAY. The number of matches tells you how many birthday calendar events the conversion will produce.
For a more visual check, load the VCF into Univik VCF Viewer. The viewer displays each contact with all fields visible contacts with a birthday show the date alongside other contact details. This makes it easy to see which contacts have birthday data and whether the dates look correct before converting.
Convert VCF to ICS on Windows
Open Univik ICS Converter. Download and install Univik ICS Converter on Windows. The tool works offline no internet connection needed.
Load the VCF file. Click Add Files and select your VCF file. The converter reads all contacts and identifies those with BDAY fields. A summary shows how many birthday events will be created before you start the conversion.
Select ICS as the output format. Choose ICS (iCalendar) from the format dropdown. Configure the event settings: event title format (for example “Sarah’s Birthday”), whether to set a reminder (typical setting is 1 day before or the morning of the event) and whether to show age in the event title.
Choose the output folder and convert. Select where to save the ICS file and click Convert. The converter produces a single ICS file containing one annual recurring event per contact birthday found. Open the file in a text editor to verify each birthday appears as a VEVENT block with RRULE:FREQ=YEARLY for the annual recurrence.
Import the ICS to Google Calendar
Open Google Calendar on a computer. Go to calendar.google.com. The ICS import option is only available on the web version the Google Calendar mobile app does not have a file import function.
Go to Settings then Import and Export. Click the gear icon (Settings) then Import and Export in the left sidebar of the Settings page.
Upload the ICS file and choose a calendar. Click Select file and choose your ICS file. Select which Google Calendar to add the birthdays to create a new calendar called “Contact Birthdays” to keep them separate from your regular events. Click Import.
Google Calendar processes the ICS file and adds one annual recurring event per birthday. The events appear across all devices signed into the same Google account phone, tablet and any calendar app synced with Google Calendar.
Import the ICS to Apple Calendar
Open the ICS file on a Mac. Double-click the ICS file in Finder. Apple Calendar opens automatically and shows a dialog asking which calendar to add the events to.
Choose a calendar and click OK. Select an existing calendar or create a new one called “Contact Birthdays.” Click OK to import. Apple Calendar adds all the birthday events at once.
Sync to iPhone via iCloud. If iCloud Calendar sync is enabled, the imported birthdays appear on your iPhone within a few minutes. Go to Settings then your name then iCloud and confirm the Calendar toggle is on.
Import the ICS to Outlook
In Outlook desktop, go to File then Open and Export then Import/Export. Choose Import an iCalendar (.ics) or vCalendar file (.vcs). Select your ICS file and click Open. Outlook asks whether to open the file as a new calendar or import the events into an existing calendar. Choose “Open as New Calendar” to keep the birthday events in a separate calendar layer this makes it easy to show or hide them independently from your regular calendar.
Frequently Asked Questions
How do I extract birthdays from a VCF file and add them to a calendar?
Convert the VCF to ICS using a converter that specifically handles BDAY field extraction. Univik ICS Converter reads each contact’s BDAY field and creates a recurring annual calendar event for each one. Import the resulting ICS file into Google Calendar, Apple Calendar or Outlook. Only contacts with a BDAY field in the VCF produce calendar events.
What if my VCF contacts don’t have birthday data?
Contacts without a BDAY field are skipped during conversion. No calendar event is created for them. Check how many of your contacts have birthday data before converting by opening the VCF in a text editor and searching for BDAY. If very few contacts have birthdays, consider adding birthdays to key contacts in your phone or address book first, then re-exporting the VCF.
Why does iPhone store birthdays without the year?
When you add a birthday to an iPhone contact using the month and day only (not entering the year), iPhone stores the BDAY field as month-day format: BDAY:–MMDD. This is valid vCard 4.0 syntax. The calendar event is still created and recurs annually on the correct date it just cannot display the person’s age because the birth year is unknown.
Can I import VCF birthdays to Google Calendar on my phone?
Not directly Google Calendar’s mobile app does not support ICS file import. Convert the VCF to ICS on a computer, then go to calendar.google.com in a desktop browser and import the ICS file from there. The imported birthdays sync automatically to the Google Calendar app on your phone within a few minutes.
How do I set birthday reminders in the ICS calendar?
When converting with Univik ICS Converter, configure the reminder setting before export. Common options are: morning of the birthday (8am alert), one day before or one week before. The reminder is embedded in each VEVENT in the ICS file as a VALARM component. Once imported, reminders can also be edited directly in your calendar application.
Will the birthday calendar update automatically when I add new contacts?
No. The ICS file is a static snapshot of your VCF at the time of conversion. If you add contacts with birthdays after the conversion, those birthdays will not appear in the calendar. Re-export your VCF file and convert it to ICS again to pick up new birthdays. Import the new ICS into a fresh calendar to avoid duplicates from the previous import.
Conclusion
Converting VCF contact birthdays to an ICS calendar takes two steps: convert with Univik ICS Converter, then import the resulting ICS file into your calendar application. The conversion only produces events for contacts that have a BDAY field check how many that is before you start so you know what to expect.
The BDAY format varies by platform. iPhone exports without a birth year use the month-day-only format which works for reminders but cannot show the person’s age. Full-date formats from Google Contacts and most Android exports work without any adjustments.
Are your contacts coming from an iPhone export, Google Contacts or a CRM? That usually tells you whether the BDAY format is likely to be full-date or month-day-only and whether age display will work in the resulting calendar.