Base62
Writing numbers with the 62 characters 0-9, a-z and A-Z, which makes short, URL-safe codes.
Definition
Base62 is like base 10, but every position has 62 possible characters instead of 10. That packs a large number into few characters without symbols that need escaping in URLs. URL shorteners use it to turn a numeric ID into a short code: 7 characters can represent about 3.5 trillion different values.
In practice
The number 125 is "21" in base62, because 125 = 2 × 62 + 1.
Learn it in context
Lessons that use this term.