*Arithmancy Puzzle Doors can be found all over Hogwarts Legacy. Although they may seem intimidating at first, they are relatively easy to solve. Make sure to solve them because there’s treasure waiting for you on the other side of the door. Here is a step-by-step guide on how to solve an Arithmancy Puzzle Door.*

## How do Arithmancy Puzzle Doors work?

Before you can **solve every Arithmancy Puzzle Door** in Hogwarts Legacy, it is important to know how they work. As you approach one of the doors in **Hogwarts**, you can **reveal the puzzle** (“F” button on a PC). Upon revealing the puzzle, you will see the following:

**Two numbers**in the middle of the triangles- A
**single questionmark “?”**and a**double questionmark “??”** - A
**number of beasts**on the puzzle and around the door

In order to open the door, you need to use **basic math**. The two question marks need to be replaced with **numbers that add up** to the **number in the center of the triangle**. By doing so, you can **solve the puzzle** and open the door.

## How to solve a Arithmancy Puzzle Door?

In order to open the door, you must **insert the missing number** into one of the question mark buttons. As shown in the screenshot below, the missing numbers and corresponding beasts are not labeled from 1 to 10, but rather from **0 to 9**. This means that the first symbol represents a value of 0, not 1.

If you want, you can locate a **cheat sheet** in the **Library Annex** near the Divination Classroom Floo Flame waypoint. However, with this guide, there is no need for the cheat sheet.

Now it’s time to find the question mark buttons. One button with **a single question mark** and another with **a double question mark**. They are usually **located close to the door**, sometimes even next to it. In case you can’t find them, use the **Revelio** spell to highlight their location. If you’re having trouble finding the buttons, a general rule of thumb is if you’ve been walking for more than 10 seconds away from the Arithmancy Puzzle Door, you’ve likely gone too far.

In the screenshot above, you can see the **current and missing values**.

For the **single question** mark, the** total value must be** **23**. We have a value of 15 and the third beast with a value of 2, adding up to 17. To reach 23, we need the **missing value of 6**, which belongs to the Rat-like beast.

For the second triangle and the **double question mark**, the **total value must be** **19**. The current value is 12. There are two Hydra-like beasts, one with a value of 3 and the other with a value of 9, totaling 12. To reach 19, we need to add the **missing value of 7**, which belongs to the Jellyfish-like beast.

The calculation for the single question mark is as follows:

15 + 2 = 17

23 – 17 = 6

Therefore, we need to find the **missing value of 6**, the **Rat-like beast**!

Now, head on over to the second triangle which needs a total value of 19. Currently at 12 (Hydra-like beasts 3 + 9). Add the **Jellyfish-like beast** with value 7 to reach 19.

The calculation for the double question mark is as follows:

9+3 = 12

19-12 = 7

Therefore, we need to find the **missing value of 7**, the **Jellyfish-like beast**!

Once you’ve selected the correct beasts from the question mark buttons, it’s time to **return to the Arithmancy Puzzle Door **and open it. If your calculations are correct, the door should open. If not, the door will bulge and you’ll need to check if you entered the correct beasts.

It’s definitely **worth solving these Arithmancy Puzzle Doors** as they contain valuable items that can aid you on your journey.