Increase File Size in KB Free
This free tool increases a file to any size you need — 20KB, 100KB, 2MB or a figure you type — by padding it with invisible data that leaves the image untouched. Everything runs in your browser, so nothing is uploaded.
Increase JPG, PNG or PDF file size
Runs entirely in this browser tab. Your file is never uploaded.
Drag a JPG, PNG or PDF file here, or
Nothing is uploaded when you pick a file.
How it works
- 1
Choose your file
Drag a file onto the tool above or click to browse. It accepts JPG, PNG and PDF files, and the file is read directly by your browser rather than sent anywhere.
- 2
Set your target size
Pick a preset from the dropdown or type an exact figure in KB or MB. The output will match that number byte for byte.
- 3
Choose how the size is added
The default pads the file with metadata areas that the file format reserves for data decoders ignore, so the image is untouched. Switch to "increase resolution" if you want more pixels as well as more bytes.
- 4
Download the result
Press the button and your browser saves the new file at exactly the size you asked for. Nothing was uploaded, so there is nothing stored anywhere for you to delete afterwards.
Why a form would reject a file for being too small
The form is not judging your image — it is judging its byte count. That rule was written to stop people uploading unreadable 5KB scans, and it has no way of telling those apart from a clean scan that simply compressed well.
Rescanning at a higher DPI would also clear the threshold, and if your scan really is hard to read that is the better fix. If it is fine and only the number is wrong, padding it is the honest shortcut: the bytes go into metadata areas that the file format reserves for data decoders ignore, and the person who opens the file sees exactly what you scanned.
Frequently asked questions
Will this reduce my image’s quality?
No. The padding goes into metadata areas that the file format reserves for data decoders ignore, so the image data is never decoded or re-compressed. What comes out is pixel-for-pixel identical, just larger on disk.
Is my file uploaded to a server?
No, and you do not have to take that on trust. Load this page, disconnect from the internet, and use the tool — it still works, which it could not do if your file had to reach a server. Nothing is transmitted, so there is nothing stored and nothing to delete afterwards.
What file formats are supported?
JPG (including .jpeg), PNG and PDF. Each one is padded using the structure its own specification reserves for data readers can ignore, so the output is always a valid file of that type.
Why would I need to increase file size instead of decrease it?
Because some upload forms enforce a minimum as well as a maximum. The minimum is meant to reject scans too low-quality to read, but it catches efficiently compressed files too. When your file is legible and simply small, making it bigger is the only thing standing between you and a successful submission.
Is this free to use?
Yes — free, with no account, no watermark, no email address and no limit on how many files you run through it. Because the work happens on your own device rather than on a server, there are no processing costs to pass on.