Solar Eclipse Calculator: the Exact Time at Your Location

The longest durations — the total eclipse of August 2, 2027, over Andalusia

The full table, city by city, with the four contacts and the Sun's altitude, is on the eclipse's own page.

How to read the result

C1 and C4

First and last contact: the Moon bites into the solar disc, then leaves it. Between the two, close to two hours during which the glasses stay on.

C2 and C3

The start and end of the central phase — totality or ring. They exist only inside the path: outside it, the calculator shows C1, maximum and C4 alone.

Maximum coverage

The fraction of the solar disc hidden at the peak. At 99 % it is still daylight; only totality uncovers the corona.

Sun's altitude

How high the Sun stands at maximum. Below 10°, the slightest ridge can hide everything: that was the problem in 2026, and it will be again in 2028.

Precision

±5-10 seconds on the contacts, from NASA/GSFC Besselian elements. The lunar limb profile can still shift C2 and C3 by one to three seconds at the edge of the path.

Method and sources

Ephemerides

The calculator first queries the IMCCE's OPALE API (Paris Observatory), INPOP19A ephemerides, accurate to about a second. If it does not answer, it falls back on the polynomial Besselian elements published by NASA/GSFC (Fred Espenak) for that eclipse.

Geometric criterion

A point lies inside the path if the minimum over time of « distance to the shadow axis minus shadow radius » turns negative. The same criterion drives a city's readout, the drawn path limits and the animated shadow: the three cannot contradict one another.

Measured precision

The Besselian fallback was cross-checked against INPOP19A for twelve cities across the three eclipses: contact times differ by 1 to 10 seconds, and path membership agrees everywhere except for one city sitting exactly on the limit. The tables above come from that same engine.