An attempt to reverse engineer the 12 digit codes found on McDonald's receipts used for the Food for Thoughts survey.
Important
Disclaimer
This project is an independent, educational analysis of McDonald's UK receipts.
It is not affiliated with, endorsed by, or connected to McDonald's International Property Company, Ltd.
The contents of this repository represent speculative research based on publicly available information, and are provided here for research and educational purposes only.
No part of this project is intended to enable or encourage misuse, fraud, or unauthorised access to McDonald's systems.
Polite notice to McLawyers: the french fries emoji, 🍟, is not McDonald's intellectual property; it's a Unicode character.
Call the script with the following arguments:
python get_code.py --store-id 1553 --order-id 1743 --purchased "2023-03-14 16:48"The above will reproduce a known historical code, 7ZWW-NGH3-ZFWJ, as shown in the following receipt:
Note the receipt contains REG 20 - this is the default value used in the script, but not all receipts have the same value.
The survey code above appears to be broken down as follows:
| Code | Decimal | Meaning |
|---|---|---|
7ZW |
1553 | Store ID. |
WNG |
2043 | Usually seems to be a combination of the "reg" number multiplied by 100 + the order ID's last two digits. In this case: (20 * 100) + 43. |
H3ZFW |
3,742,128 | Date/time of purchase (represented as number of minutes since 2016-02-01 00:00). |
J |
23 | Check digit (Luhn mod N algorithm; uses 25 as a base). |
Values are encoded using the following base 25 system:
| Decimal | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Base 25 | C | M | 7 | W | D | 6 | N | 4 | R | H | F | 9 | Z | L | 3 | X | K | Q | G | V | P | B | T | J | Y |
- A non-exhaustive list of store IDs is included (stores.tsv). You can also find store IDs by inspecting the return data from the McDonald's restaurant locator or by simply checking receipts.
- Discussion on Reverse Engineering Stack Exchange where this was originally posted: https://reverseengineering.stackexchange.com/questions/32129/mcdonalds-receipt-codes