Explain it like I'm 12
Solstices and equinoxes are the seasonal turning points of Earth’s orbit. Choose the year and event, then the calculator shows the usual approximate civil date and the matching season for your hemisphere.
Seasons and Solstices Calculator
Look up the approximate equinox or solstice date for a year and see which season begins in each hemisphere.
Why people use this calculator
- Check approximate solstice and equinox dates.
- Explain why Northern and Southern Hemisphere seasons are opposite.
- Plan seasonal content, school notes or astronomy reminders before checking exact UTC times.
Common mistakes
- Mixing astronomical seasons with meteorological seasons.
- Forgetting that exact event times vary by year and timezone.
- Using Northern Hemisphere season labels for Southern Hemisphere locations.
Citation sentence
CalculationTime maps selected equinox and solstice events to approximate Gregorian dates and labels the corresponding season by hemisphere.
Source references
- NASA - Solstices and equinoxes — astronomical season explainer
- NOAA SciJinks - Seasons — season and tilt explanation
Formula
Foundation date table: March equinox ≈ March 20, June solstice ≈ June 21, September equinox ≈ September 22, December solstice ≈ December 21. Hemisphere changes the season label.
Worked example
For 2026 in the Southern Hemisphere, the June solstice is approximately 2026-06-21 and marks the start of winter by the common astronomical-season convention.
Professional note
Master’s Tip: write whether you mean meteorological seasons or astronomical seasons. This page uses the equinox/solstice convention.
Regional and unit assumptions
Standard or basis: transparent Gregorian calendar arithmetic using UTC midnight. No legal, holiday or regional filing standard is claimed.
Assumptions and limitations
- Approximate civil dates are used for foundation planning.
- Exact astronomical event times vary by year and timezone.
- Northern and Southern Hemisphere season labels are opposite for solstices and equinoxes.
Methodology & Accuracy
How this calculator is checked
CalculationTime pages are built around visible arithmetic: the formula, assumptions, worked example and practical limitations are shown so the result can be checked rather than simply trusted.
Formula used
Foundation date table: March equinox ≈ March 20, June solstice ≈ June 21, September equinox ≈ September 22, December solstice ≈ December 21. Hemisphere changes the season label.
Standard or basis
Standard or basis: transparent Gregorian calendar arithmetic using UTC midnight. No legal, holiday or regional filing standard is claimed.
Where a calculator follows a named legal, trade or industry standard, that standard is cited visibly. Otherwise the page uses transparent general arithmetic and states its limits.Master's Tip
Master’s Tip: write whether you mean meteorological seasons or astronomical seasons. This page uses the equinox/solstice convention.
Related calculators
Questions
Are solstices and equinoxes on the same date every year?
They stay close to the same dates, but exact UTC times vary by year.
Why do hemispheres have opposite seasons?
Earth’s axial tilt points one hemisphere more toward the Sun while the other is tilted away.
Is this meteorological or astronomical season timing?
This calculator uses the astronomical convention based on equinoxes and solstices.
Calculation note
Season calculators are simple at the civil-date level and precise only when the exact astronomical instant is needed. The useful part is keeping hemisphere, convention and event name visible together.