Choosing a phone PIN code that's easy to remember might be a time-saver. It's also a potential security risk.

If your phone or another device is lost or stolen, an easily-guessed PIN code makes it easier for someone to unlock the device and access the personal or financial information stored within. The same goes for your ATM PIN, if you lose your debit card.

And the most common four-digit PIN found in data breaches is also a highly guessable one: the simple "1234," according to a recent Australian Broadcasting Corporation analysis of data from HaveIBeenPwned.com, which which has a database of more than 320 million passwords and PINs aggregated from past leaks.

Some PINs on the report's list are only slightly more complex. Thirty of the 50 most commonly leaked four-digit PINs start with "19" or "20," potentially indicating someone's birth year — relatively simple to decode, if you once posted about your birthday on social media.

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Other common formats include repeating numbers, like "1111" and "0000." There's also "1342," a rearrangement of the most-common PIN, and "2580," which draws a straight line down the middle of most numerical keypads.

Here are the 50 most common four-digit PIN codes, according to the analysis:

1. 1234
2. 1111
3. 0000
4. 1342
5. 1212
6. 2222
7. 4444
8. 1122
9. 1986
10. 2020
11. 7777
12. 5555
13. 1989
14. 9999
15. 6969
16. 2004
17. 1010
18. 4321
19. 6666
20. 1984
21. 1987
22. 1985
23. 8888
24. 2000
25. 1980
26. 1988
27. 1982
28. 2580
29. 1313
30. 1990
31. 1991
32. 1983
33. 1978
34. 1979
35. 1995
36. 1994
37. 1977
38. 1981
39. 3333
40. 1992
41. 1975
42. 2005
43. 1993
44. 1976
45. 1996
46. 2002
47. 1973
48. 2468
49. 1998
50. 1974

If any of the above PIN codes match your own, you'd be wise to consider changing things up. Your phone and debit card will be more secure if you choose a more obscure PIN, even if it isn't as easy for you to remember at first.

Data breaches affected more than 1.3 billion people around the world last year, according to the Identity Theft Resource Center. The Federal Trade Commission suggests using at least a six-digit PIN for your devices, if possible, and use any available fingerprint or facial scanning technologies for added security.

Some devices might limit the length of your PIN options, so the U.S. Cybersecurity & Infrastructure Security Agency recommends you pick a random and unique PIN, avoiding obvious patterns or sequences with personal connections.

Be careful using the same PIN for multiple devices or accounts, too: If someone correctly guesses one of your PINs, they'll likely try to use it again if they can.

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