| token | → | chr − (control | t‑special)+ |
| comment | → | lparen (ctext quoted‑pair | comment)* rparen |
| parameter | → | attribute eq attr‑val |
| attribute | → | token |
| attr‑val | → | token | quoted‑string |
| hex | → | digit | hx |
| chr | → | digit | hx | alpha | ht | dq | cr | lf | ctl | sp | colon | semicolon | comma | dot | lparen | rparen | langle | rangle | lbracket | rbracket | lbrace | rbrace | slash | backslash | eq | ch |
| text | → | octet − control |
| ctext | → | text − (lparen | rparen) |
| quoted‑string | → | dq (qd‑text | quoted‑pair)* dq |
| qd‑text | → | text − dq |
| quoted‑pair | → | backslash chr |
| control | → | ht | cr | lf | ctl |
| t‑special | → | lparen | rparen | langle | rangle | at | comma | semicolon | colon | backslash | dq | slash | lbracket | rbracket | quest | eq | lbrace | rbrace | sp | ht |
| octet | → | chr | oct |
| lws | → | ((cr | lf)? (sp | ht))+ |