Quick Identification Guide
Use these tells to quickly identify number encoding types:
| Pattern | Likely Encoding | Example |
|---|---|---|
| Numbers 1-26 | A1Z26 | 8 5 12 12 15 |
| 65-90 or 97-122 | ASCII | 72 69 76 76 79 |
| Only 0 and 1 | Binary | 01001000 |
| 0-9 and A-F | Hexadecimal | 48 45 4C 4C 4F |
| Only 0-7 | Octal | 110 105 114 114 117 |
| Ends with = or == | Base64 | SGVsbG8= |
A1Z26 (Alphabet Position)
The simplest letter-number encoding: A=1, B=2, ... Z=26.
How to Recognise
- All numbers are between 1 and 26
- Numbers often separated by spaces, commas, or dashes
- No letters present in the code itself
Example:
8 5 12 12 15 23 15 18 12 4
Decodes to: HELLO WORLD
Tool: A1Z26 Converter
ASCII Encoding
ASCII assigns numbers to characters. Key ranges for letters:
Uppercase A-Z
65-90
Lowercase a-z
97-122
How to Recognise
- Two-digit numbers, mostly in the 65-90 or 97-122 range
- Space is 32, common punctuation in 30s-40s
- Numbers often in pairs or triplets
Example:
72 69 76 76 79
Decodes to: HELLO
Tool: ASCII Converter
Binary Encoding
Binary represents everything as sequences of 0s and 1s. Each character typically uses 7 or 8 bits (digits).
How to Recognise
- Only contains 0 and 1
- Usually in groups of 7 or 8 digits
- Often very long sequences
Example (8-bit):
01001000 01000101 01001100 01001100 01001111
Decodes to: HELLO
Quick Decoding Tip
Binary starting with 0100 is usually uppercase (A-Z). Binary starting with 0110 is usually lowercase (a-z).
Tool: Binary Converter
Hexadecimal
Hex uses base-16 with digits 0-9 and letters A-F. Each character is typically represented by two hex digits.
How to Recognise
- Only contains 0-9 and A-F (or a-f)
- Usually in pairs of characters
- Often starts with 0x or has spaces between pairs
Example:
48 45 4C 4C 4F
Decodes to: HELLO
Key Values
Tool: Hex Converter
Octal (Base-8)
Octal uses digits 0-7. Less common but still appears in puzzles.
How to Recognise
- Only contains digits 0-7 (never 8 or 9)
- Usually in groups of 3 digits
- May be preceded by a leading 0
Example:
110 105 114 114 117
Decodes to: HELLO
Tool: Octal Converter
Base64
Base64 encodes data using 64 characters (A-Z, a-z, 0-9, +, /). Common in tech puzzles.
How to Recognise
- Mix of uppercase, lowercase, numbers
- Often ends with = or == (padding)
- Character set: A-Z, a-z, 0-9, +, /
- Length is typically a multiple of 4
Example:
SGVsbG8gV29ybGQ=
Decodes to: Hello World
Tool: Base64 Decoder
Quick Decision Process
1. Check character set:
• Only 0 and 1? → Binary
• Only 0-7? → Octal
• 0-9 and A-F only? → Hexadecimal
• Mixed alphanumeric + ends with =? → Base64
2. Check number ranges:
• All numbers 1-26? → A1Z26
• Numbers 65-90 or 97-122? → ASCII
3. Still unsure?
• Try each decoder tool—one will produce readable text!
Pro Tips
- Check the highest number. If max is 26, it's A1Z26. If max is around 122, it's ASCII.
- Count digits per group. Binary uses 7-8, hex uses 2, octal uses 3.
- Look for common words. If decoding gives gibberish, try a different method.
- Consider layered encoding. Sometimes text is encoded twice (e.g., Base64 then A1Z26).