Restoring from Seed XOR

Restoring from Seed XOR

In your Coldcard device go to:

1. Advanced

2. Danger Zone

3. Seed functions

4. Seed XOR

5. Restore Seed XOR

6. OK

7. Enter the words from list A

   • At the 24th word, The Coldcard will display a short list of words for you to choose the correct word from.

8. Repeat for list B

You must have both parts in order to restore your seed phrase. The order in which you enter them (either seed XOR A or B) does not matter.

If restoring on existing Coldcard:

• The imported seed XOR will only remain temporarily.

• You will be asked if you want to use the existing seed by pressing on 1 - DON’T, press OK

If restoring on new Coldcard:

Follow the instructions below if you are restoring your seed on a new, uninitialized Coldcard device.

1. Import Existing

2. Seed XOR

3. Enter one of the parts (lis A or B)

4. When done, press on 1 to enter the next part

5. Enter the other list of words

6. Confirm that the 24th word of your original seed phrase is correct

7. Press 2 to complete the import

To verify the imported seed:

Use this to see the backup stored in the device and if it matches the original that you have written down.

1. Advanced

2. Danger Zone

3. Seed functions

4. View Seed Words

5. OK

Restoring your backup with Seed XOR by hand

It is possible to recreate your original backup using the two seed XOR word lists by hand. Follow the intructions below to do so:

1. Using this worksheet, enter the words from the two lists that have been generated using seed XOR on your Coldcard.

2. Using this wordlist, write down the 3-digit hex code associated with each word in your worksheet.

3. Once lists A and B have been written down in the worksheet, use the table in your worksheet to complete the A + B row.

To do so, associate the hex digits of each word from list A with those from list B.

Whether you look up the row or column first does not change anything since it will produce the same value.

Enter the digit that you obtain from the table in your worksheet. At the end of the process, you will have a new hex code.

Using the wordlist and the newly generated hex codes, retrieve the words that form your seed phrase.