How Many Days Until Summer?
A summer countdown page computes the time difference between the current date and the next occurrence of June 21, providing the remaining days, hours, minutes, and seconds.
View the live countdown to the first day of Summer. Find out exactly how many days, weeks, hours, and seconds are left until June 21.
Quick Answer
Find the exact count of days remaining until the next summer solstice (June 21) computed live from today's date.
Loading live countdown...
Examples
Summer Solstice Date
June 21 (Approx.)
Solstice Event
Astronomical Event
How it works
The live timer computes the differences between now and June 21 in local timezone milliseconds:
Countdown · Days = (June 21 - Today) / 86,400,000
How the Days Until Summer are Calculated
To calculate the number of days until the start of summer, find the difference in milliseconds between the solstice target date (June 21 at midnight) and the current local system date. Since the summer solstice occurs annually, if June 21 of the current year has already passed, the calculation shifts to next year's June 21 date.
Math: (Target Date Time − Current Time) in Milliseconds ÷ 1,000 ÷ 60 ÷ 60 ÷ 24 = Days Remaining
Astronomical vs. Meteorological Seasons
Seasons can be divided in two ways:
- Astronomical Summer: Starts on the summer solstice (June 20–22) and ends on the autumn equinox (September 21–23). This is governed by the Earth's tilt relative to the sun.
- Meteorological Summer: Defined by climatologists as the three warmest calendar months: June, July, and August. It begins on June 1 and ends on August 31.
Related Date & Holiday Countdowns
Explore our other dynamic date and seasonal countdown tools:
- How Many Days Until Halloween? — count down to October 31.
- How Many Days Until Christmas? — count down to December 25.
- How Many Days Until Thanksgiving? — check the date of the next US Thanksgiving.
- Date Calculator — add or subtract days to calculate custom target dates.
Related Calculators
More tools from Conversions