Remembering Friends' Birthdays Throughout the Year
Jules wants to call Ari on July 9 and mail a card to Morgan for July 15.
Special dates, made simple
Everyday Examples
Explore illustrative situations with reproducible inputs and practical workflows.
Special Date Tracker
Organizing Family and Work Anniversaries
Rowan keeps a family gathering on December 31, 2026 and a work anniversary that began January 3, 2020 in the same browser.
Keeping a Household Birthday List Without Duplicate Records
A shared shopping trip can cover several birthdays, but each person still needs a separate record.
Saving a Friend's Birthday When the Year Is Unknown
A friend gives you May 6 as their birthday but keeps their age private.
Keeping Two Anniversaries on the Same Day
A wedding anniversary and a work anniversary can share a date while requiring different preparation.
Rescheduling a Party Without Moving the Birthday
A birthday falls on October 9, but the party moves from October 10 to October 17, 2027.
Grouping Family Dates Without Losing Their Individual Meaning
A household wants a family-only review that includes a reunion and a moving day, but excludes work records.
Editing a Work Anniversary After a Role Change
A promotion does not necessarily replace the day someone joined an organization.
Filtering Similar Names Across Event Categories
Searching a person's name can return a birthday, graduation, and anniversary.
Recovering an Accidentally Changed Date From a Backup
A saved event was changed from August 14 to August 24, 2027, and the correct date still exists in a JSON backup.
Birthday Countdown
Checking the Gap Before a Summer Birthday
You need to decide whether there is time to mail a card for a June 8 birthday.
Recognizing a Birthday That Is Today
A countdown of zero should mean the occasion is here.
Finding the Next Birthday Just After This Year's Has Passed
A June 8 birthday has already passed when you review the list on June 9, 2027.
Counting From New Year's Eve to a January Birthday
A January 3 birthday can disappear from a December-only planning view even when it is only a few days away.
Comparing Both Common-Year Rules for a February 29 Birthday
A February 29 birthday needs an agreed observance date in 2027.
Counting Down to a Year-End Birthday Without Adding a Year
You know a friend's birthday is December 31 and want to see the remaining days without recording their age.
Checking a Child's Age Before the Next Birthday
An invitation for a seventh birthday should use the age at the birthday rather than the child's age when you prepare the invitation.
Returning to February 29 in a Leap Year
A birthday observed on March 1 in common years should return to February 29 when that date exists.
Using a Custom Reference Date for Birthday Planning
You are preparing a schedule for a trip that begins before a birthday.
Understanding Birthday Days Without Converting Them to Hours
A birthday one calendar day away does not always mean 24 hours remain until the celebration.
Age Calculator
Reading a Calendar Age With Years, Months, and Days
A keepsake needs a precise calendar age rather than just a completed-year number.
Measuring a Baby's Age Across a Short February
A baby born January 31, 2027 reaches a monthly age marker in a month that has no 31st.
Dating a Photograph Taken Before a Birthday
A photograph labeled “June 2025” may have been taken before or after the subject's birthday.
Preparing a Future Birthday Caption
A scrapbook is being prepared ahead of a thirtieth birthday.
A Leap-Year Birth That Does Not Need a February 29 Rule
Being born in a leap year does not automatically require a special birthday policy.
Comparing Age Policies for a February 29 Birth
Someone born February 29, 2020 is being described on February 28, 2025.
Checking Age After a January 31 Birthday
A month-end birth exposes why calendar months cannot be treated as fixed thirty-day units.
Using Total Days Lived for a Personal Milestone
A person wants to mark 10,000 completed days since January 1, 2000.
Finding the Weekday of Birth for an Album
A family album prompt asks which weekday someone was born on.
Counting Age Across a Century Without a Leap Day
A commemorative record spans 1900, a year that is divisible by four but is not a leap year.
Anniversary Calculator
Tracking a Couple's Relationship Anniversary
Quinn and Taylor became a couple on June 18, 2021.
Checking the First Wedding Anniversary on Its Eve
An anniversary card is being prepared for a wedding on September 12, 2026.
Choosing Between a Civil Ceremony and a Wedding Celebration
A couple had a civil ceremony on May 10, 2020 and a celebration on August 22, 2020.
Separating a First Date From Becoming a Couple
A couple remembers both their first date on February 14, 2023 and the day they became a couple on March 10, 2023.
Reading Completed Months in a Friendship Anniversary
A friendship began on November 30, 2024, and a reunion is planned for February 28, 2027.
Measuring Time in a Company and Time in a Role
A person joined a company on March 18, 2022 and started a new role on September 1, 2026.
Following an Anniversary Across New Year's Day
A work anniversary falls on January 3, and a review happens on December 30.
Checking a February 29 Anniversary Under Both Policies
An event began February 29, 2020, and the anniversary is being reviewed on February 28, 2025.
Finding a Fiftieth Anniversary Without Guessing the Day Total
A family is planning a fiftieth wedding anniversary for June 15, 2027.
Checking the Next Anniversary When It Falls Today
A reminder list needs to include an anniversary that is happening today.
Days Together Calculator
Planning a 1,000-Day Relationship Celebration
Sam and Robin count January 1, 2024 as Day 1 of their relationship.
Starting a Relationship Count on the First Day
A couple wants the first day of their relationship to appear as Day 1.
Comparing the First Date With the Relationship Start
A first meeting was February 1, 2027, a first date was February 14, and the couple agreed they were together on March 10.
Recognizing Inclusive Day 100 as Today's Milestone
A couple checks their milestone on April 10, 2027 after starting on January 1.
Finding Day 365 When a Leap Day Intervenes
A relationship began March 1, 2023.
Following a Relationship Count Across a Leap Day
A couple wants to record the first few days after a February 28, 2024 start.
Counting Calendar Days Across a Clock Change
Two people want a date-based count across a weekend when their location changes clocks.
Reconstructing a Relationship Count on an Old Trip
A photo book needs the relationship day number during a trip on August 20, 2024.
Planning Preparation Around a Relationship Milestone
A couple wants to celebrate inclusive Day 100 and finish an album two weeks before it.
Correcting a Relationship End Date Before the Start
A reversed input can produce an error that looks like a missing result.
Milestone Date Calculator
Tracking a Child's Important Milestones
A parent wants a private note for 500 elapsed days after January 1, 2024.
Finding 100 Completed Days After a Birth
A family wants a private record of 100 completed days after a birth on January 1, 2024.
Converting Relationship Day 200 Into a Date Offset
A couple counts January 1, 2027 as Day 1 and wants the date of Day 200.
Choosing Between Wedding Day 500 and 500 Completed Days
A wedding took place October 1, 2025.
Finding 1,000 Elapsed Days Together
A relationship began January 1, 2024, and the celebration is intended to mark 1,000 complete days.
Marking 5,000 Days Since a Personal Turning Point
A personal project began January 1, 2010, and its owner wants to mark 5,000 completed days without translating that number into approximate years.
Checking a Custom 10,000-Day Target With a Reverse Calculation
A person wants to validate a 10,000-day milestone before engraving its date.
Working Backward Across New Year's Day for a Booking
An event is scheduled for January 3, 2027 and the booking needs confirmation fourteen calendar days beforehand.
Crossing February 29 With a Fixed Day Offset
A 100-day interval starting in early 2024 crosses a leap day.
Comparing Two Milestones Without Resetting the Start
A couple wants both a 200-day and a 500-day marker from January 1, 2027.
Celebration Planner
Planning a 10th Wedding Anniversary
A couple married September 12, 2015 and wants to invite a few friends to dinner on September 13, 2025.
Planning a Birthday With a Small Spending Limit
A birthday on May 16, 2027 has a USD 60 spending limit.
Preparing a Family Birthday Gathering Without Losing the Guest Count
An eight-person family meal is planned for August 22, 2027.
Planning a Couple's Anniversary Outing With Two Cost Scopes
A couple is choosing an anniversary outing for June 18, 2027.
Organizing a Child's Birthday Tasks Around a Venue Booking
A child's party on July 12, 2027 has several tasks finished while the venue is still unbooked.
Keeping Gift Possibilities Separate From Purchases
A gift list contains a book, a puzzle, and a meal voucher, but the budget should include only the option actually being bought.
Keeping a Multi-Guest Plan Clear Without an RSVP Feature
An October 17, 2027 celebration has six invited guests and two uncertain responses.
Finding and Resolving an Over-Budget Celebration
A November 20, 2027 plan has a USD 100 limit, but estimated costs exceed it.
Arranging Final Tasks in the Days Before a Celebration
A celebration is on January 3, 2027 and the final review happens December 30, 2026.
Keeping Two Celebrations in the Same Month Financially Separate
Two celebrations fall on April 4 and April 13, 2027.
Calendar & Exporter
Organizing Birthdays for a Family of Five
A household of five wants one private birthday list and a smaller calendar they can share with relatives.
Building a Yearly Special Dates Calendar
A household wants to view a yearless February 29 birthday, a July 10, 2027 reunion, and a December 8, 2027 graduation together before making travel plans.
Reviewing a Month of Birthdays Without Hiding Other Records
A household has birthdays on April 4 and April 13, 2027, plus a one-time family meal on April 17.
Filtering Anniversary Categories Without Losing a First Date
A calendar contains a relationship anniversary on June 18, a work anniversary on January 3, and a first date on February 14.
Exporting One All-Day Event to an ICS File
A one-time graduation on December 8, 2027 needs to be copied into another calendar without exporting the rest of the household's dates.
Checking a Mixed ICS Export Before Importing Everything
A test file with one ordinary annual birthday and one one-time event can reveal import problems before a larger calendar is copied.
Understanding Where an Annual Export Series Begins
A work anniversary began January 3, 2020.
Exporting a February 29 Birthday With a Finite Horizon
A birthday should appear on March 1 in common years and February 29 in leap years.
Reviewing a CSV Date List Before Opening a Spreadsheet
A spreadsheet review can help find inconsistent titles, but the CSV should not be treated as a complete recovery backup.
Restoring a JSON Backup Without Losing Newer Plans
An older backup has two dates and one plan.