Example 1
- Date: 1990-05-15
Tuesday · Mars
Tuesday maps to Mars in the Chaldean table.
Planetary day calculator
From the weekday you read the classical planet: Sunday Sun, Monday Moon, then Mars, Mercury, Jupiter, Venus, Saturn.
Here the day planet comes from the weekday. This tool is for entertainment and learning, not fortune-telling or life advice. It does not replace personal, medical or financial decisions. Also try the moon phase and daily color.
Result
Pick a date to see the planetary day.
How it works
A planetary day in Western tradition pairs the seven weekdays with the seven classical “planets” (Sun and Moon counted with the five visible planets).
The Chaldean weekday order is fixed: Sunday → Sun, Monday → Moon, Tuesday → Mars, Wednesday → Mercury, Thursday → Jupiter, Friday → Venus, Saturday → Saturn. We do not compute planetary hours or sunrises here.
The method is explicit. From an ISO date we take the weekday (Sunday = 0 .. Saturday = 6) and map it to a table row. It is a calendar label, not an ephemeris.
Example: 15 May 1990 is a Tuesday → Mars. 1 January 2000 is a Saturday → Saturn. 8 August 1988 is a Monday → Moon.
Another case: 7 July 1977 (Thursday → Jupiter), 22 March 2024 (Friday → Venus), 24 March 2024 (Sunday → Sun). The same planet returns every seven days.
Weekday names in many European languages still carry these associations (e.g. Saturday / Saturn). Here we show the classical Greco-Chaldean list in an educational form.
This is not a moon phase (synodic cycle) or a Sun sign. Do not confuse it with daily color, which is a separate date label in our toolkit.
Magical schools often go further (planetary hours from sunrise). Calcboxer’s goal is simpler: a repeatable weekday→planet map without location.
Treat the result as a drill on the week and planet lore. Do not read it as fortune-telling, a forecast or a day instruction.
Formula
dow = weekday(date) (0=Sunday .. 6=Saturday)
planet = Chaldean_table[dow]
Table: Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn.
No planetary hours, time zone math or geographic latitude.
How to use the calculator
- Type the value in “Date” using the unit printed on that label, not a different scale.
- Click Calculate or wait for the live result.
- Leave a blank field blank: the calculator errors out and does not fake a zero.
- The metric/US switch relabels units and does not convert a number you already typed.
- Optionally pair with the moon phase for the same date.
Suggested uses
- Learn the classical weekday → planet map.
- Compare seven consecutive dates in one week.
- Workshop entertainment: mythic labels without fortune-telling.
- Quickly check a “day planet” before reading historical texts.
- Calendar practice beside moon phase and Sun sign.
- Start a talk about planetary day vs planetary hour.
Examples
Example 2
- Date: 2000-01-01
Saturday · Saturn
Saturday → Saturn.
Example 3
- Date: 1988-08-08
Monday · Moon
Monday → Moon.
Example 4
- Date: 1977-07-07
Thursday · Jupiter
Thursday → Jupiter.
Example 5
- Date: 2024-03-22
Friday · Venus
Friday → Venus.
Example 6
- Date: 2024-03-24
Sunday · Sun
Sunday → Sun.
Example 7
- Date: 12
Result on the card after fill
What is planetary day calculator of 12?
Example 8
- Date: 24
Result on the card after fill
What is planetary day calculator of 24?
Related calculators
Frequently asked questions
What is a planetary day?
A classical label: each weekday is paired with one of the seven Chaldean planets (Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn).
Which order do you use?
Sunday-Sun, Monday-Moon, Tuesday-Mars, Wednesday-Mercury, Thursday-Jupiter, Friday-Venus, Saturday-Saturn.
Do you compute planetary hours?
No. Here we only map the weekday. Planetary hours need sunrise and a location.
Which time zone?
We take the weekday from the calendar date (UTC from ISO). For ordinary civil dates the result matches the local weekday.
Is this a daily fortune?
No. The calculator is for entertainment and learning. It does not replace personal decisions or professional advice.
Why is Saturday Saturn?
In classical tradition Saturday is Saturn’s day (hence English Saturday). It is a historical label, not a physics measurement.
What next after the result?
Check moon phase, zodiac sign and daily color for the same date. Together they give a wider, still entertainment-only calendar context.
What if “the first field” is blank?
Nothing calculates. A blank field is an error, not a hidden zero. Type a number or clear the form and start from an example further down the page.
Which planet is 1990-05-15, and which is 2000-01-01?
15 May 1990 is Tuesday, Mars. 1 January 2000 is Saturday, Saturn. Order: Sunday Sun, Monday Moon, Tuesday Mars.
Does a blank date fill today planetary day?
No. A blank field calculates nothing. Type 1990-05-15 to see Tuesday and Mars. Zero in a date is not Saturday either.