How to Compress an Image to 50 KB, 100 KB or 200 KB

By the Docly team · Updated October 22, 2026

Many online forms, such as exam applications, job portals, visa sites and bank KYC pages, reject files above a fixed size. The limit is often between 20 KB and 200 KB, while a photo straight from a phone camera can be 3 to 8 MB. This guide explains why that gap exists and how to close it without wrecking the picture.

Why photos are so large

A phone photo can contain 12 million pixels or more, and each pixel needs data. A passport-style photo shown on a form only needs a few hundred pixels across. That extra resolution is where most of the size goes, so reducing it is usually the biggest saving.

The three things that control file size

Quality. JPG and WebP are lossy formats. Lower quality means more compression and a smaller file, but too low causes blocky patches around text and faces.
Dimensions. Halving the width and height cuts the pixel count to a quarter. Check what pixel size the form asks for and do not go larger than that.
Format. Photos are smallest as JPG or WebP. PNG keeps every detail and is far larger for photographs, so use it only when a form demands it or for sharp graphics.

Step by step with the Docly Image Compressor

Open the Image Compressor and add your photo, signature or scanned document.
Choose JPG as the output unless the form says otherwise.
Type the maximum size in the Target size box, for example 100 for 100 KB.
If the result is still too large, or the form states a size in pixels, enter a Max width.
Press Compress images and check the size shown next to the file name.
Download the file and upload it to the form.

The tool searches for the highest quality that fits your target, and shrinks the image automatically only if even the lowest quality is too big. Everything runs in your browser, so your photo and ID documents are not uploaded to our servers.

Tips for better results

Crop the image first if there is a lot of empty background. A tighter crop leaves more bytes for the face or text.
For a signature, sign on white paper in dark ink, in good light. Clean scans compress much smaller than shadowy ones.
Do not compress a file that was already compressed several times. Start again from the original each time you need a different size.
If text on a scanned document becomes hard to read, raise the target size a little instead of lowering quality further.
To check the size on Windows, right-click the file and choose Properties. On a phone, open the file details in your gallery or files app.
Keep the original photo. You may need a higher quality version later.

Common questions

Why is my result a little over the target? A very small target can be impossible for a large, detailed image. Add a max width so the dimensions shrink too.

Can I convert PNG to JPG here? Yes. Choose JPG as the output. Transparent areas turn white because JPG cannot store transparency. You can also use the Image Converter for simple format changes.

This guide is for general information. It is not financial, legal or professional advice.