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[Date Calculator] How many days left until ○○ ? / Free travel tools

Date Calucrator Web API

[Date Calculator] How many days left until ○○ ?

How many days until 〇〇? This is a free day calculation web app that allows you to calculate the number of days.

"When will the tickets go on sale for the plane I want to take?"

“What is the start date for booking mileage award tickets?”

"How many days until the big day?"

..and so on.

There are surprisingly many situations where you want to know the number of days until an important day. For example, in the case of travel, the reservation start date for airline tickets and mileage award travel is determined to be how many days before the departure date, etc., but you end up wondering, "When exactly is XX days ago?" and when the sales and reservations start. There are times when you miss out on a flight ticket and can't get a great deal.

We have created a "day calculation" web app that allows you to easily calculate the number of days until such an important day. There are four methods for calculating the number of days: "Number of days remaining until the specified date", "How many days before the specified date", "How many days after the specified date", and "How many days from the specified date to the specified date?". The number of days that can be calculated is 20 years before and after today, for a total of 40 years.

For your reference, we have also provided the flight ticket release dates and mileage award travel reservation dates for airlines such as ANA and JAL below, so be sure to use them when planning your next trip!

*The airline calculates "XX days before the departure date" without including the start date, so this days calculator also does not include the start date. Please use the information on this number of days calculation page as a guide only.

How many days left until the day below?

What date is X day(s) before a specified date?

day(s) before

What date is X day(s) after a specified date?

day(s) after

How many days between

and

Today : -- --
Booking start date for major airline tickets
All Nippon Airways / ANA
  • International flights : 9:00 AM 355 days before
  • Domestic flights : 9:30 AM 355 days before
  • Mileage award travel : Same as ticket sale date for both domestic and international flights
Apr 08 (Tue) 2025 : after 355 days from today
Japan Airlines / JAL
  • International flights : 10:00 AM 360 days before
  • Domestic flights : 9:30 AM 330 days before
  • Mileage award travel : Same as ticket sale date for both domestic and international flights
Apr 13 (Sun) 2025 : after 360 days from today
Delta Airlines
  • International flights : 331 days before
  • Domestic flights : 331 days before
  • Mileage award travel : Same as ticket sale date for both domestic and international flights
Mar 15 (Sat) 2025 : after 331 days from today
United Airlines
  • International flights : 337 days before
  • Domestic flights : about 11 months before
  • Mileage award travel : Same as ticket sale date for both domestic and international flights
Mar 21 (Fri) 2025 : after 337 days from today