Magstripe Card Reader – 22/03/2025

I was browsing on EBay when I came across this listing:

I was intrigued and so I decided to purchase it.

By observing the device, the way it works is that there is a spring-loaded Magnetic reader, that when is pushed down by the swiping of a card, records the data.

This is the spring-loaded magnetic reader.

Once the device records the data, it enters the keystrokes of the data into the connect computer (via USB-A).

The device acts as a keyboard or HID (Human-Interface-Device). Once a card is swiped, it “types”the data really fast into the connected computer and then simulates pressing ENTER.

However, the data is sort of a jumbled mess. I swiped my debit card on it and here is what it typed (sensitive data redacted)

%B################^LASTNAME/FIRSTNAME. ^YYMM******** ****************?;################=********************?

I have made a python program to parse/extract the relevant data (Card no, Cardholder name, Expiry) and display it.

Python Code:

import tkinter as tk

from tkinter import messagebox

def parse_magstripe(data):

try:

if data.startswith('%B') and '?' in data:

# Split the data into tracks

track1, track2 = data.split('?')[:2]

# Parse Track 1

track1_parts = track1.split('^')

card_number = track1_parts[0][2:] # Remove %B prefix

cardholder_name = track1_parts[1].strip()

exp_date = track1_parts[2][:4]

exp_date = f'{exp_date[2:4]}/{exp_date[0:2]}'

return card_number, exp_date, cardholder_name

else:

raise ValueError("Invalid magstripe data")

except Exception as e:

messagebox.showerror("Error", f"Failed to parse card data: {e}")

return None, None, None

def on_card_swipe(event=None):

data = entry.get()

card_number, exp_date, cardholder_name = parse_magstripe(data)

if card_number:

card_number_label.config(text=f"Card Number: {card_number}")

exp_date_label.config(text=f"Exp Date (MM/YY): {exp_date}")

cardholder_name_label.config(text=f"Cardholder Name: {cardholder_name}")

entry.delete(0, tk.END)

app = tk.Tk()

app.title("Magstripe Card Reader Parser")

app.geometry("400x200")

entry = tk.Entry(app, font=('Arial', 14))

entry.pack(pady=10)

entry.bind("<Return>", on_card_swipe)

card_number_label = tk.Label(app, text="Card Number:", font=('Arial', 12))

card_number_label.pack(pady=5)

exp_date_label = tk.Label(app, text="Exp Date (MM/YY):", font=('Arial', 12))

exp_date_label.pack(pady=5)

cardholder_name_label = tk.Label(app, text="Cardholder Name:", font=('Arial', 12))

cardholder_name_label.pack(pady=5)

app.mainloop()

When using the program, you should first click on the Text Input box at the top. Then all you need to do is swipe your Credit/Debit card in the Magstripe Card Reader and the relevant data should be displayed.

The downside of the magnetic strip is that it does not contain the CVC/CVV code, so you can not easily process online transactions using just the data from the Magnetic Strip.

You can also scan any other cards with a magnetic strip, such as gift cards. However the above program is only for Debit/Credit cards, so it is best to open a text editor such as Notepad or Notepad++ to see the data.

Once swiping, the device plays a short and sharp BEEP! sound.

Thank you for reading to the end, and please email any questions or feedback to [email protected]

Have a lovely day :)