PHP 8.0.26 Released!


(PHP 5, PHP 7, PHP 8)

iconv_mime_decode_headersDecodes multiple MIME header fields at once


iconv_mime_decode_headers(string $headers, int $mode = 0, ?string $encoding = null): array|false

Decodes multiple MIME header fields at once.



The encoded headers, as a string.


mode determines the behaviour in the event iconv_mime_decode_headers() encounters a malformed MIME header field. You can specify any combination of the following bitmasks.

Bitmasks acceptable to iconv_mime_decode_headers()
Value Constant Description
1 ICONV_MIME_DECODE_STRICT If set, the given header is decoded in full conformance with the standards defined in » RFC2047. This option is disabled by default because there are a lot of broken mail user agents that don't follow the specification and don't produce correct MIME headers.
2 ICONV_MIME_DECODE_CONTINUE_ON_ERROR If set, iconv_mime_decode_headers() attempts to ignore any grammatical errors and continue to process a given header.


The optional encoding parameter specifies the character set to represent the result by. If omitted or null, iconv.internal_encoding will be used.

Return Values

Returns an associative array that holds a whole set of MIME header fields specified by headers on success, or false if an error occurs during the decoding.

Each key of the return value represents an individual field name and the corresponding element represents a field value. If more than one field of the same name are present, iconv_mime_decode_headers() automatically incorporates them into a numerically indexed array in the order of occurrence. Note that header names are not case-insensitive.


Version Description
8.0.0 encoding is nullable now.


Example #1 iconv_mime_decode_headers() example

= <<<EOF
Subject: =?UTF-8?B?UHLDvGZ1bmcgUHLDvGZ1bmc=?=
Date: Thu, 1 Jan 1970 00:00:00 +0000
Message-Id: <>
Received: from localhost (localhost []) by localhost
    with SMTP id example for <>;
    Thu, 1 Jan 1970 00:00:00 +0000 (UTC)
Received: (qmail 0 invoked by uid 65534); 1 Thu 2003 00:00:00 +0000


$headers =  iconv_mime_decode_headers($headers_string0"ISO-8859-1");

The above example will output:

    [Subject] => Prüfung Prüfung
    [To] =>
    [Date] => Thu, 1 Jan 1970 00:00:00 +0000
    [Message-Id] => <>
    [Received] => Array
            [0] => from localhost (localhost []) by localhost with SMTP id example for <>; Thu, 1 Jan 1970 00:00:00 +0000 (UTC) (envelope-from
            [1] => (qmail 0 invoked by uid 65534); 1 Thu 2003 00:00:00 +0000


See Also

add a note

User Contributed Notes 1 note

12 years ago
If you need lower-case header-names (as I read the documentation case is not guranteed) try something like


= <<<EOF
Subject: =?UTF-8?B?UHLDvGZ1bmcgUHLDvGZ1bmc=?=
Date: Thu, 1 Jan 1970 00:00:00 +0000
Message-Id: <>
Received: from localhost (localhost []) by localhost
    with SMTP id example for <>;
    Thu, 1 Jan 1970 00:00:00 +0000 (UTC)
Received: (qmail 0 invoked by uid 65534); 1 Thu 2003 00:00:00 +0000


$headers iconv_mime_decode_headers($headers_string, 0, "ISO-8859-1");

$headers = array_combine(array_map("strtolower", array_keys($headers)), array_values($headers));

To Top