How to reduce a photo to 100 KB (or any size limit)

Government portals, exam registrations and job applications often limit photo and signature uploads to 20 KB, 50 KB, 100 KB or 200 KB. A phone photo is usually 2–6 MB, which is 20 to 60 times too big. Here's how to get under the limit reliably.

Why phone photos are so big

File size depends mostly on two things: the number of pixels (width × height) and the compression quality. Reducing the pixel size has the biggest effect. A 4,000-pixel-wide photo has about 16 times as many pixels as a 1,000-pixel one.

Step by step

1. If the form needs a specific shape (square, passport size), crop first with Crop image.
2. Open Compress image and choose your photo.
3. Set a maximum width: try 800 pixels for 100 KB, or 600 for 50 KB.
4. Keep JPG and set quality around 70%.
5. Download and check the size shown. If it's still too big, lower the width or quality a little and try again.

Typical starting points

• Under 200 KB: about 1,200 px wide, quality 75%.
• Under 100 KB: about 800 px wide, quality 70%.
• Under 50 KB: about 600 px wide, quality 60%.
• Under 20 KB (signatures): about 400 px wide, quality 60%.

These are starting points; the result depends on the picture. Detailed backgrounds need more space than plain ones.

Check the form's other rules

Many forms also require exact pixel dimensions, a plain background or a particular file type (usually JPG). Read the instructions carefully; a photo under the size limit can still be rejected for other reasons.

Privacy

ID photos and signatures are sensitive. DocNova compresses them in your browser without uploading them.

Frequently asked questions

Will compression make my photo blurry?

At sensible settings, most people can't see the difference on screen. Problems start below about 50% quality or when the width is reduced too far for the text in a document to stay readable, so always zoom in and check.

PNG or JPG?

For photos, JPG is much smaller. PNG is lossless and best for logos and screenshots with sharp edges, but it rarely gets small enough for strict limits.