How to compress a photo or signature to 20 KB or 50 KB
Open Resize photo to KB, add the photo or the picture of your signature, pick 20 KB or 50 KB and press Resize it. It is made smaller in your browser, so your face and your signature never leave your phone.
Resize photo to KBFree. Nothing is uploaded.
How to do it
- Open Resize photo to KB and add the photo, or the picture of your signature.
- Pick the size the form allows: 20 KB, 50 KB, or Other to type your own.
- Leave Keep its shape chosen, or type the width and height if the form gives them in pixels.
- Press Resize it and read the new size and pixels in the result line.
- Save the picture and upload that one, not the original.
What the form is asking for
Upload forms for exams, jobs, scholarships, banks and government services usually limit two things about a picture. The weight, in KB, is how much space the file takes. The size in pixels is how many dots wide and tall it is. Some forms give only the weight, some give both, and a few also ask for the JPG format by name.
A photo straight from a phone camera weighs a few MB and is thousands of pixels across, so it is far over a 20 KB or 50 KB limit before you begin. The numbers you need are on the form itself, usually beside the upload button or in its instructions. Read them there: every form sets its own, and this tool simply meets whatever you choose.
Why under 20 KB usually means fewer pixels
A JPEG gets lighter as its quality goes down, but only up to a point. Below a certain quality the picture breaks into square blocks and smudges, and a face or a signature stops looking right long before it gets small enough for 20 KB. A twelve-megapixel phone photo simply holds too many pixels to fit in 20 KB at any quality worth uploading.
So the tool works in two steps. First it tries the best quality and steps down only as far as the limit needs. If even the lowest quality that still looks right is too heavy, it keeps that quality and takes away pixels instead, only as many as it must. The result line then says so, for example made smaller to fit, with the size the photo was before. A few hundred pixels across is still a clear face on screen, and a signature of that width reads cleanly.
If the form also gives a size in pixels, choose Width × height and type it. The picture is cut from the middle to that shape and made exactly that size, and the quality is chosen to fit the KB. If those pixels cannot fit under the limit and stay clear, the result says so rather than quietly changing them.
Scanning a signature on white paper
Sign on plain white paper with no lines, in black or dark blue ink, with a pen that writes a firm, even line. A ballpoint that skips or a pencil gives a faint, broken signature that gets worse as the picture gets smaller. Leave clear space around it, so nothing else from the page ends up in the photo.
Photograph it in daylight, holding the phone straight above the paper so the signature is not slanted and your hand casts no shadow. Then crop the photo close around the signature in your phone’s gallery before you add it. Clean white paper costs almost nothing in KB, while a grey, shadowy background costs a great deal, so a tidy photo fits under 20 KB with far more detail to spare. For a whole page of paper rather than one signature, use Scan, which straightens the sheet and cleans up the light.
Check the result before you upload
Open the saved picture and zoom in. A face should be sharp around the eyes, and a signature’s lines should be unbroken. The new file’s name ends with the limit, such as (under 20 KB), which makes it easy to pick the right one in the form’s file picker rather than the original from the camera.
Here 1 KB is 1,000 bytes, slightly smaller than counting in 1,024s, so a picture made under 20 KB here is also under 20 KB on a form that counts the other way. If a form still says the file is too big, check that you chose the new file; then make it again with Other and a slightly lower figure, such as 18. If it says the pixel size is wrong, type the exact width and height it gives.
A worked example
An application asks for a recent photo under 50 KB and a signature under 20 KB, both as JPG. Open Resize photo to KB, add the photo, pick 50 KB, keep Keep its shape and press Resize it. The result line gives the old and new size and the pixels, perhaps saying the photo was made smaller to fit. Save it.
Tap Start over, add the cropped photo of your signature, pick 20 KB and press Resize it again. Save that too, then upload each file to its own box on the form. Neither left your phone until you uploaded it yourself.
What the phone hid in the photo
Phones store details inside every photo: the camera, the date and time, and often the exact place it was taken. A form does not need any of that. A picture made here is saved afresh and carries none of it, and the result line says what was taken out, such as location and camera details. That is one less thing about you sitting on somebody else’s server.
Questions people ask
Why not just set the quality very low?
A very low quality turns a face into blocks and a signature into smudges, and an unclear photo is a common reason for an application to be sent back. The tool stops at a quality that still looks right and takes away pixels instead.
Is 1 KB 1,000 or 1,024 bytes here?
1,000 bytes, the smaller of the two. So a picture made under 20 KB here is under 20 KB on any form, however it counts.
Can I do the photo and the signature together?
Yes, if both need the same limit: add both and each comes out on its own, under the size you chose. For different limits, make one, tap Start over, and make the other.
The form wants a PDF, not a JPG.
Make the JPG here first, then turn it into a PDF with Images to PDF. If a PDF is over its limit, Compress has a To a size setting; see compress a PDF to 100 KB.
Does it work on an iPhone?
Yes, in Safari. Photos are usually handed over as JPEG. If one arrives in the HEIC format and this browser cannot read it, the tool says so; setting Camera, Formats to Most Compatible fixes it for future photos.
Is my photo uploaded anywhere?
No. It is made smaller in your browser, on your own device, and the tool keeps working with the internet switched off.
Your file stays on your device. Foolscap does the work inside your browser, so nothing is uploaded and there is nothing for anyone to keep. How you can check