What this tool does

This checker compares two people's birth charts and explains how they fit together, for love, friendship or work. It calculates both charts properly from the birth details, then looks at how your Sun, Moon, Venus and Mars signs combine and at the strongest links between the two charts, known as synastry aspects, before giving you a warm, balanced reading and a score for the kind of relationship you chose.

It is meant as a bit of fun and a prompt for reflection, not a prediction or a verdict on any relationship.

When to use it

Use it when you are curious about a new romance, a long partnership, an old friendship or a new colleague. It works with just two birth dates, which is enough for the Sun, Venus, Mars and usually the Moon. Adding birth times and towns gives each person a rising sign and a more precise Moon, which makes the comparison richer.

How it works

You choose both birth dates, and if you know them, the birth times and the towns or cities of birth. The tool finds each place and its time zone, including any summer time on that date, and calculates where the planets were for each person. It then works out the aspects between the two charts, such as one person's Venus sitting opposite the other's Sun, and the reading explains the tightest of these. If a Moon could be in either of two signs because the birth time is unknown, the reading says so rather than guessing. Place names come from GeoNames.

You do not need to give your name or email to use it. Take it in the spirit it is meant: real relationships are built on how you treat each other, not the stars.