What the Zodiac Mercury Retrograde Calendar does
This calendar lists every Mercury retrograde period for any year from 1900 to 2100: the date and time Mercury turns retrograde, the date it turns direct, the zodiac degree of each station, and the pre- and post-retrograde shadow periods, shown in your own time zone and ready to export as a calendar file or CSV. It also answers the everyday question at the top: is Mercury retrograde right now?
The dates are not copied from a list. The page computes Mercury's position as seen from Earth for every day of the year and finds the moments its motion along the zodiac stops and reverses. For 2025 and 2026 the station times agree with NASA JPL Horizons to within about an hour. That Mercury retrograde disrupts plans and phones is astrological belief rather than astronomy, and the page keeps the two apart.
How to use it
- Enter a year, or click one of the example years.
- Choose the time zone the dates should be shown in. It defaults to your browser's zone.
- Read the headline for today's status and the next retrograde start.
- Use the table: pre-shadow start, the retrograde station with its sign and degree, the direct station with the length of the retrograde, and the end of the post-shadow.
- Click "Add to calendar" to download an .ics file with each retrograde and shadow as all-day events, or download the CSV.
Reading the results
Turns retrograde is the station when Mercury appears to stop and begin moving backwards against the stars; turns direct is when it stops again and resumes its normal motion. In between, it retraces part of the zodiac, typically 10 to 15 degrees.
The pre-shadow begins when Mercury first reaches the degree where it will later turn direct, and the post-shadow ends when it gets back to the degree where it turned retrograde. The shadows are an astrological convention built on real positions.
Most years have three retrograde periods, each lasting about three weeks, and some have a fourth beginning in late December. That adds up to roughly 60 to 70 days, about 18% of the year.
If a station falls near midnight, its date depends on the time zone. That is the most common reason two published lists disagree by a day.
Worked example: the three retrogrades of 2026
Mercury turns retrograde on 26 February 2026 at about 06:51 UTC at 22 deg 34' Pisces and turns direct on 20 March at about 19:41 UTC at 8 deg 29' Pisces, 22.5 days later. The pre-shadow starts on 11 February, when Mercury first passes 8 deg 29' Pisces.
The second retrograde runs from 29 June (26 deg 15' Cancer) to 23 July (16 deg 19' Cancer), and the third from 24 October (20 deg 58' Scorpio) to 13 November (5 deg 01' Scorpio).
JPL Horizons, sampled hourly, has Mercury's longitude stop rising at 07:00 UTC on 26 February 2026 and stop falling at 20:00 UTC on 20 March, so the computed station times are within the hour. In India (UTC+05:30) the first station is 26 February at 12:21.
Formulas and scoring rules
- Mercury's longitude
geocentric apparent ecliptic longitude from Schlyter's elements of date, with light-time, aberration and nutation- Daily motion
v(t) = (lambda(t + 0.05 d) - lambda(t - 0.05 d)) / 0.1 d- Stations
v sampled daily; each sign change of v is located by bisection to about a secondFrom positive to negative: turns retrograde. From negative to positive: turns direct.- Shadows
pre-shadow start = last time before the retrograde station that lambda = lambda(direct station); post-shadow end = first time after the direct station that lambda = lambda(retrograde station)
Limitations: what the result does not prove
- Mercury's position is accurate to about 1 arc-minute, which puts station times within about an hour; the shadow boundaries, where Mercury moves fast, are accurate to minutes.
- Calendar exports are all-day events in the chosen time zone; the exact UTC moment is in the event description and the CSV.
- Years 1900 to 2100 only.
- Mercury retrograde is a line-of-sight effect. Claims that it causes miscommunication, travel delays or broken gadgets are astrological tradition, not something that has been demonstrated.
Privacy: where your data goes
Everything you paste, type or drop is processed in this browser tab. It is not uploaded, logged, stored or sent to analytics. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- NASA JPL Horizons - solar system ephemeris used to check positions - checked 19 Sep 2026
- NASA Science - Mercury
- Paul Schlyter - How to compute planetary positions
Frequently asked questions
Is Mercury in retrograde right now?
The headline answers it for today, using your device's clock: it says whether Mercury is retrograde, in a shadow period or direct, and when the next retrograde begins or the current one ends.
When are the Mercury retrograde dates for 2026?
26 February to 20 March, 29 June to 23 July, and 24 October to 13 November 2026 (UTC dates). Choose 2026 and your time zone to see the exact local times, signs and shadow periods.
What is the Mercury retrograde shadow period?
The pre-shadow is the stretch before the retrograde when Mercury moves over the degrees it will later retrace; the post-shadow is the stretch afterwards when it moves back over them. Each lasts about two weeks. It is an astrological idea defined by real positions.
Why does Mercury look like it goes backwards?
Mercury orbits the Sun faster than Earth. When it passes between Earth and the Sun, our line of sight to it swings backwards against the distant stars for about three weeks, the same way a car you overtake seems to slide backwards.
How many times a year is Mercury retrograde?
Usually three times, occasionally four, because the cycle repeats every 116 days. Each retrograde lasts about 21 to 24 days, so Mercury spends roughly a fifth of the year retrograde.
Why do retrograde calendars differ by a day?
Because the stations are moments, not days. A station at 23:00 UTC is already the next day in Asia, and different sites use different time zones. Set the zone here to the one you live in and the dates will be right for you.
Last reviewed by the A2Z.Tools team against the sources listed above.
