Free tool · UK
Astrology Houses Calculator (UK, Placidus)
Enter your birth date, time and place of birth for your twelve house cusps in the PlacidusThe house system we use to draw the twelve house cusps. It is the most common one in Western astrology.Learn more → system and the house each planet falls in. We also flag the planets that would move house if your time were half an hour out either way.
Narrow it down with your life events
A calculator needs a time. Our report works the other way round: it tests the possible times against the dated events of your life. We aren't taking UK orders yet; leave your email and we'll send one message when we open.
How the houses are calculated
The chart is split into twelve houses. The first cusp is the ascendant and the tenth is the Midheaven; the others are placed by the Placidus method, the most common in Western astrology. Placidus cusps can't be calculated near the polar circles, so this tool covers places up to 66° of latitude.
Planets move slowly, but the cusps turn about a degree every four minutes. A planet close to a cusp can change house within half an hour, even when the rising sign stays the same. The list of planets that change house shows where a time that is a little off could matter.
Born in the UK?
A full birth certificate in England and Wales normally doesn't show the time of birth, except for twins and other multiple births. Scotland is different. Read how to find your birth time in the UK and whether a birth certificate shows the time.
Short answers
- Which house system does this calculator use?
- Placidus, the most common house system in Western astrology.
- Why would a planet change house if my time is a little off?
- The house cusps move with the ascendant, about a degree every four minutes. A planet that sits near a cusp can end up on the other side of it within half an hour.
- Does it allow for British Summer Time?
- The time you enter is read as the clock time at your place of birth in the UK, using the historical time zone rules for that date, including British Summer Time and the other changes to UK clocks over the years. If the clocks went forward and your time falls in the skipped hour, the calculator tells you.
More free tools
- Ascendant calculatorYour rising sign and Midheaven, and how long your sign lasts.
- Moon sign calculatorFind out if your birth time can change your Moon sign.
- Sun, Moon and rising calculatorThe big three, and which one depends on the time.
- Midheaven calculatorYour MC sign and how far it moves in two hours.
- How to find your rising signThree ways, from a calculator to a range check.
- How to find out what time you were bornWhere to look for your birth time, and what to do if you can't find it.
- Birth chart without a birth timeWhat you can use and what needs the time.
- Free range checkEvery rising sign that fits inside a range of hours.
Want more than a range? See what a full report looks like in the sample report, or get notified when UK orders open.
Astrology is a symbolic practice, not a science. Your report gives the most consistent birth-time window for the events you share. It is not a certified birth time.