URL Encoding
URLs can be transmitted over the Internet only using the ASCII character set. If a URL has characters outside the ASCII set, the URL must be converted.
Non-ASCII characters are replaced with a "%", which is followed by hexadecimal digits.
URLs cannot contain spaces. URL encoding commonly replaces a space with %20, or a plus "+" sign.
| ASCII Character | URL-encoding | Description |
|---|---|---|
| NUL | %00 | null character |
| SOH | %01 | start of header |
| STX | %02 | start of text |
| ETX | %03 | end of text |
| EOT | %04 | end of transmission |
| ENQ | %05 | enquiry |
| ACK | %06 | acknowledge |
| BEL | %07 | bell (ring) |
| BS | %08 | backspace |
| HT | %09 | horizontal tab |
| LF | %0A | line feed |
| VT | %0B | vertical tab |
| FF | %0C | form feed |
| CR | %0D | carriage return |
| SO | %0E | shift out |
| SI | %0F | shift in |
| DLE | %10 | data link escape |
| DC1 | %11 | device control 1 |
| DC2 | %12 | device control 2 |
| DC3 | %13 | device control 3 |
| DC4 | %14 | device control 4 |
| NAK | %15 | negative acknowledge |
| SYN | %16 | synchronize |
| ETB | %17 | end transmission block |
| CAN | %18 | cancel |
| EM | %19 | end of medium |
| SUB | %1A | substitute |
| ESC | %1B | escape |
| FS | %1C | file separator |
| GS | %1D | group separator |
| RS | %1E | record separator |
| US | %1F | unit separator |