A free synastry chart from two people's birth details — see the cross-aspects between your planets, a 0–100 compatibility score, and readings for the key angles at a glance.

Synastry is the art of laying two birth charts side by side to see how one person's planets meet the other's. Enter both partners' date of birth, birth time, and birth city, and Giggleus calculates the cross-aspects between your planets — where your Sun, Moon, Venus, Mars, and the rest form a conjunction, trine, square, opposition, or sextile with your partner's. Every meaningful angle comes with a clear, easy-to-read interpretation, so you can actually see where the two of you flow and where you spark.

From all those contacts we build a single 0–100 compatibility score with a simple band, plus a rundown of the standout aspects driving it. Sun–Moon harmony, a Venus–Mars pull, or a tense Saturn square — you'll see which planets are doing the talking in your relationship. It's a rich, at-a-glance read on romantic chemistry, friendship, or any pairing you're curious about.

This synastry calculator is 100% free with no sign-up and no payment — just enter two sets of details and read the chart. Don't know an exact birth time? You can still compare sign placements, simply skipping the parts that need a precise time. The astronomical math is accurate, while the interpretations are strictly for fun and reflection, never a verdict on your fate.