How to check file size using javascript

You can't get the file size of local files with javascript in a standard way using a web browser. But if the file is accessible from a remote path, you might be able to send a HEAD request using Javascript, and read the Content-length header, depending on the webserver. JavaScript cannot access files on the local computer for security reasons, even to check their size. The only thing you can do is use JavaScript to submit the form with the file field to a server-side script, which can then measure its size and return it.

See here for a similar question posted. To get the file size of pages on the web I built a javascript bookmarklet to do the trick. It alerts the size in kb's. Change the alert to a prompt if you want to copy the filesize. How are we doing? Please help us improve Stack Overflow.

Take our short survey. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 11 years, 7 months ago. Active 1 year, 5 months ago. Viewed k times. They somehow manage to show uploading progress bar — Andrey. Do you have a webserver able to access C:?

If your OS is on C: , I advise against that, but first things first. Add a comment. Active Oldest Votes. Andy E Andy E k 80 80 gold badges silver badges bronze badges. Andrey: Other web applications use Java or Flash.

I updated my answer with a link to the popular SWFUpload. Andrey Other script tools such as Flash, ActiveX, etc can access the local file system. Alternatively, certain server-side techniques can be used to monitor file upload progress and feed that information back when javascript requests it — Mark Baker. Andrey: that is not a cross-browser solution either. I don't think Firefox exposes the fileSize property, it's certainly not part of the standard.

It might also only work for valid images and not other files. Show 6 more comments. Veer Veer 4, 1 1 gold badge 12 12 silver badges 11 11 bronze badges. If you could access the file system of a user with javascript, image the bad that could happen. Sarfraz Sarfraz k 70 70 gold badges silver badges bronze badges. Try this one. Jaumzera Jaumzera 2, 24 24 silver badges 42 42 bronze badges. Mukhil P Mukhil P 11 3 3 bronze badges. Andrey using flash or a php module which can count bytes or similar.

Andrey there are module s for php to let you query the server to see how far the upload has progressed. Check if the size follows your desired criteria. Listen for the change event on the input. Get the size of the file by this. You can round off the obtained value as well by toFixed method.

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Hey geek! The constant emerging technologies in the world of web development always keeps the excitement for this subject through the roof. But before you tackle the big projects, we suggest you start by learning the basics. Now at it's lowest price ever! Previous How to get the input file size in jQuery?

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