| ID | Name | Flags | Description | 
|---|---|---|---|
| FILTER_SANITIZE_EMAIL | "email" | Remove all characters except letters, digits and !#$%&'*+-=?^_`{|}~@.[]. | |
| FILTER_SANITIZE_ENCODED | "encoded" | FILTER_FLAG_STRIP_LOW,FILTER_FLAG_STRIP_HIGH,FILTER_FLAG_ENCODE_LOW,FILTER_FLAG_ENCODE_HIGH | URL-encode string, optionally strip or encode special characters. | 
| FILTER_SANITIZE_MAGIC_QUOTES | "magic_quotes" | Apply addslashes(). | |
| FILTER_SANITIZE_NUMBER_FLOAT | "number_float" | FILTER_FLAG_ALLOW_FRACTION,FILTER_FLAG_ALLOW_THOUSAND,FILTER_FLAG_ALLOW_SCIENTIFIC | Remove all characters except digits, +- and optionally .,eE. | 
| FILTER_SANITIZE_NUMBER_INT | "number_int" | Remove all characters except digits, plus and minus sign. | |
| FILTER_SANITIZE_SPECIAL_CHARS | "special_chars" | FILTER_FLAG_STRIP_LOW,FILTER_FLAG_STRIP_HIGH,FILTER_FLAG_ENCODE_HIGH | HTML-escape '"<>& and characters with ASCII value less than 32, optionally strip or encode other special characters. | 
| FILTER_SANITIZE_FULL_SPECIAL_CHARS | "full_special_chars" | FILTER_FLAG_NO_ENCODE_QUOTES, | Equivalent to calling htmlspecialchars() with ENT_QUOTESset. Encoding quotes can
         be disabled by settingFILTER_FLAG_NO_ENCODE_QUOTES. Like htmlspecialchars(), this
         filter is aware of the default_charset and if a sequence of bytes is detected that
         makes up an invalid character in the current character set then the entire string is rejected resulting in a 0-length string.
         When using this filter as a default filter, see the warning below about setting the default flags to 0. | 
| FILTER_SANITIZE_STRING | "string" | FILTER_FLAG_NO_ENCODE_QUOTES,FILTER_FLAG_STRIP_LOW,FILTER_FLAG_STRIP_HIGH,FILTER_FLAG_ENCODE_LOW,FILTER_FLAG_ENCODE_HIGH,FILTER_FLAG_ENCODE_AMP | Strip tags, optionally strip or encode special characters. | 
| FILTER_SANITIZE_STRIPPED | "stripped" | Alias of "string" filter. | |
| FILTER_SANITIZE_URL | "url" | Remove all characters except letters, digits and $-_.+!*'(),{}|\\^~[]`<>#%";/?:@&=. | |
| FILTER_UNSAFE_RAW | "unsafe_raw" | FILTER_FLAG_STRIP_LOW,FILTER_FLAG_STRIP_HIGH,FILTER_FLAG_ENCODE_LOW,FILTER_FLAG_ENCODE_HIGH,FILTER_FLAG_ENCODE_AMP | Do nothing, optionally strip or encode special characters. This
         filter is also aliased to FILTER_DEFAULT. | 
       When using one of these filters as a default filter either through your ini file
       or through your web server's configuration, the default flags is set to 
       FILTER_FLAG_NO_ENCODE_QUOTES.  You need to explicitly set
       filter.default_flags to 0 to have quotes encoded by default. Like this:
       
Example #1 Configuring the default filter to act like htmlspecialchars
filter.default = full_special_chars
filter.default_flags = 0
| Version | Description | 
|---|---|
| 5.2.11/5.3.1 | Slashes (/) are removed by FILTER_SANITIZE_EMAIL. Prior they were retained. |