By default, PHP allows uploading maximum 2 MB file on the server. But you can change the maximum size of file upload as per your requirement. Using the PHP configuration file [php.ini], you can increase or decrease the file upload size in PHP.
The upload_max_filesize and post_max_size variable’s value need to be modified in php.ini file. Follow the below steps to increase the limit of file upload size in PHP.
- Open the php.ini file in the text editor.
- Search for upload_max_filesize variable and specify the size which you want to increase.
upload_max_filesize = 128M
- Search for post_max_size variable and specify the size which you want to increase. [Basically it same as
upload_max_filesizevariable value]post_max_size = 128M
- Once done, save the modified php.ini file and restart the server.
Uploading a file from a web form in PHP is easy. The online manual provides a Handling File Uploads section, and there are several articles on sitepoint.com, including How To Handle File Uploads With PHP by Kevin Yank.
One of the most popular uses is image uploads. Your users can submit photographs from a form without resorting to FTP or other convoluted methods. HTML5 and Flash also permit drag and drop, so the operation is likely to become easier as browsers evolve.
This is where the problems can begin. Camera manufacturers continually brag that they have a larger set of megapixels than their competitors. It’s all rubbish, of course — unless you’re a professional photographer or need to print extremely large images, anything over 4MP is fairly pointless and lens quality is much more important. However, even low-end compacts have 12MP and mobile phones have more than 5MP. The result is that a typical snapshot can easily be 6MB in size.
By default, PHP permits a maximum file upload of 2MB. You can ask users to resize their images before uploading but let’s face it: they won’t. Fortunately, we can increase the limit when necessary.
Two PHP configuration options control the maximum upload size: upload_max_filesize and post_max_size. Both can be set to, say, “10M” for 10 megabyte file sizes.
However, you also need to consider the time it takes to complete an upload. PHP scripts normally time-out after 30 seconds, but a 10MB file would take at least 3 minutes to upload on a healthy broadband connection [remember that upload speeds are typically five times slower than download speeds]. In addition, manipulating or saving an uploaded image may also cause script time-outs. We therefore need to set PHP’s max_input_time and max_execution_time to something like 300 [5 minutes specified in seconds].
These options can be set in your server’s php.ini configuration file so that they apply to all your applications. Alternatively, if you’re using Apache, you can configure the settings in your application’s .htaccess file:
php_value upload_max_filesize 10M
php_value post_max_size 10M
php_value max_input_time 300
php_value max_execution_time 300
Finally, you can define the constraints within your PHP application:
ini_set['upload_max_filesize', '10M'];
ini_set['post_max_size', '10M'];
ini_set['max_input_time', 300];
ini_set['max_execution_time', 300];
PHP also provides a set_time_limit[] function so you don’t need to set max_execution_time directly.
Setting the options in your PHP code is possibly more practical, since you can extend the execution time and increase the file size when your application is expecting a large upload. Other forms would revert to the default 30-second time-out and 2MB limit.
Do you have any other tips for uploading large files in PHP?
The MAX_FILE_SIZE item cannot specify a file size greater than the file size that has been set in the upload_max_filesize in the php.ini file. The default is 2 megabytes.
If a memory limit is enabled, a larger memory_limit may be needed. Make sure you set memory_limit large enough.
If max_execution_time is set too small, script execution may be exceeded by the value. Make sure you set max_execution_time large enough.
Note: max_execution_time only affects the execution time of the script itself. Any time spent on activity that happens outside the execution of the script such as system calls using system[], the sleep[] function, database queries, time taken by the file upload process, etc. is not included when determining the maximum time that the script has been running.
Warning
max_input_time sets the maximum time, in seconds, the script is allowed to receive input; this includes file uploads. For large or multiple files, or users on slower connections, the
default of 60 seconds may be exceeded.
If post_max_size is set too small, large files cannot be uploaded. Make sure you set post_max_size large enough.
The max_file_uploads configuration setting controls the maximum number of files that can uploaded in one request. If more files are uploaded than
the limit, then $_FILES will stop processing files once the limit is reached. For example, if max_file_uploads is set to 10, then $_FILES will never contain more than 10 items.
Not validating which file you operate on may mean that users can access sensitive information in other directories.
Due to the large amount of directory listing styles we cannot guarantee that files with exotic names [like containing spaces] are handled properly.
A developer may not mix normal input fields and file upload fields in the same form variable [by using an input name like foo[]].
amalcon _a_t_ eudoramail _d_o_t_ com ¶
18 years ago
Note that, when you want to upload VERY large files [or you want to set the limiters VERY high for test purposes], all of the upload file size limiters are stored in signed 32-bit ints. This means that setting a limit higher than about 2.1 GB will result in PHP seeing a large negative number. I have not found any way around this.
Nirmal Natarajan ¶
12 years ago
If using IIS 7.0 or above, the Request Filtering is enabled by default and the max allowed content length is set to 30 MB.
One must change this value if they want to allow file uploads of more than 30 MB.
Sample web.config entry:
The above setting will allow 300 MB of data to be sent as a request. Hope this helps someone.
adrien.nizon+phpnet at gmail dot com ¶
6 years ago
[Editor's note: to be more precise, MAX_FILE_SIZE can't exceed PHP_INT_MAX before PHP 7.1.]
Please note that the field MAX_FILE_SIZE cannot exceed 2147483647. Any greater value will lead to an upload error that will be displayed at the end of the upload
This is explained by the related C code :
if [!strcasecmp[param, "MAX_FILE_SIZE"]] {
max_file_size = atol[value];
}
The string is converted into a long int, which max value is... 2147483647
Seems to be corrected since php-7.1.0beta3 [//github.com/php/php-src/commit/cb4c195f0b85ca5d91fee1ebe90105b8bb68356c]
admin at creationfarm dot com ¶
19 years ago
The macintosh OS [not sure about OSx] uses a dual forked file system, unlike the rest of the world ;-]. Every macintosh file has a data fork and a resource fork. When a dual forked file hits a single forked file system, something has to go, and it is the resource fork. This was recognized as a problem [bad idea to begin with] and apple started recomending that developers avoid sticking vital file info in the resource fork portion of a file, but some files are still very sensitive to this. The main ones to watch out for are macintosh font files and executables, once the resource fork is gone from a mac font or an executable it is useless. To protect the files they should be stuffed or zipped prior to upload to protect the resource fork.
Most mac ftp clients [like fetch] allow files to be uploaded in Macbinhex, which will also protect the resource fork when transfering files via ftp. I have not seen this equivilent in any mac browser [but I haven't done too much digging either].
FYI, apple does have an old utility called ResEdit that lets you manipulate the resource fork portion of a file.
bohwaz ¶
7 days ago
Please be advised that setting a large post_max_size or upload_max_filesize for a complete server or a complete virtual host is not a good idea as it may lead to increased security risks.
The risk is that an attacker may send very large POST requests and overloading your server memory and CPU as it has to parse and process those requests before handling them to your PHP script.
So it's best to limit changing this setting to some files or directories. For example if I want to /admin/files/ and /admin/images/ I can use:
php_value post_max_size 256M
php_value upload_max_filesize 256M
I also require the request to have a cookie to avoid basic attacks. This will not protect you against attacks coming from non-authenticated users, but may delay any attack.
This setting can be used in Apache server configuration files, and .htaccess files as well.
dg at artegic dot de ¶
12 years ago
In case of non-deterministic occurence of the UPLOAD_ERR_PARTIAL error: The HTTPD [e.g. Apache] should respond with a 'Accept-Ranges: none' header field.
anders jenbo pc dk ¶
14 years ago
A responce to admin at creationfarm dot com, Mac OS X and Windows running on a NTFS disk also uses a multi stream file system. Still only the data stream in transfared on http upload. It is preferable to pack Mac OS X files in .dmg files rathere then zip but the avarage user will find zip much easir and they are supported on more platforms.
tjaart at siam-data-services dot com ¶
17 years ago
Took me a while to figure this one out...
I think this is actually a header problem, but it only
happens when doing a file upload.
If you attept a header["location://...] redirect after
processing a $_POST[''] from a form doing a file upload
[i.e. having enctype="multipart/form-data"], the redirect
doesn't work in IE if you don't have a space between
location: & http, i.e.
header["location://...] vs
header["location: //...]
===================================
Your file:
===================================
This only happens if all of the following are true:
header["location://...] with no space
Form being processed has enctype="multipart/form-data"
Browser=IE
To fix the problem, simply add the space.
Hope this helps someone else.
morganaj at coleggwent dot ac dot uk ¶
18 years ago
Here is another that may make your upload fall over. If you are using Squid or similar proxy server make sure that this is not limiting the size of the HTTP headers. This took me weeks to figure out!
tomcashman at unitekgroup dot com ¶
19 years ago
For apache, also check the LimitRequestBody directive.
If you're running a Red Hat install, this might be set in /etc/httpd/conf.d/php.conf.
By default, mine was set to 512 KB.
oliver dot schmidt at drehsinn dot de ¶
15 years ago
If you want to use open_basedir for securing your server [which is highly recommended!!!] remember to add your tmp dir to the open_basedir value in php.ini.
Example: open_basedir = :/tmp
[Tested on gentoo Linux, Apache 2.2, PHP 5.1.6]
sebastian at drozdz dot ch ¶
19 years ago
It's important that the variable 'open_basedir' in php.ini isn't set to a directory that doesn't not includes tempupload directory