How to Compress a PNG to Under 100 KB (2026 Step-by-Step)

How to Compress a PNG to Under 100 KB (2026 Step-by-Step)

A fresh PNG screenshot from a 4K display lands somewhere between 1.5 and 4 MB. If your CMS, email signature, or chat platform caps attachments at 100 KB, you need a 95%+ reduction — but you don't have to sacrifice the image to get there. This guide walks through the exact decisions to compress any PNG under 100 KB while keeping it readable.

We'll use paste-to-download.com/compress throughout — a free browser-based compressor that handles PNG, WebP, and AVIF with no upload and no per-image limit.

Why 100 KB is Hard for PNG

PNG is a lossless format. Every pixel is preserved exactly. That's why your 4K screenshot is 3 MB — the algorithm can't throw anything away. To get under 100 KB you generally need to:

• Switch to a lossy format (WebP, AVIF, or lossy PNG variants)
• Reduce the pixel dimensions
• Strip metadata and color profiles

If you must keep PNG (e.g. uploading to a system that rejects WebP), there are still tricks — palette quantization and lossy PNG can cut size by 80% — but the easy win is switching format.

Step 1: Pick the Right Output Format

Default choice: WebP at quality 80 unless transparency or platform compatibility forces you elsewhere.

Step 2: Reduce Dimensions Before Encoding

A common mistake is dialing down quality before resizing. A 4000×3000 image at quality 30 still beats a 1600×1200 image at quality 80 in file size — but the quality-30 version looks awful. Always resize first:

• Web hero / blog image: 1600 px on the long edge
• Inline content image: 1200 px
• Thumbnail / avatar: 400-800 px
• Email signature: 300 px

Open /resize before /compress if you have many oversized files — the two tools chain naturally.

Step 3: Apply the Right Quality Setting

Quality slider math (rough averages for a real-world photo):

• Quality 95: file ~80% of original, indistinguishable
• Quality 85: file ~50% of original, indistinguishable at normal viewing
• Quality 75: file ~30% of original, slight softening on close inspection
• Quality 65: file ~20% of original, visible banding on gradients
• Quality 50: file ~12% of original, obvious artifacts on text and photos

Start at 75. If the result is still over 100 KB, drop in 10-point steps. Below 50 the image starts looking visibly bad — at that point go back to step 2 and reduce dimensions more aggressively instead.

Step 4: Strip Metadata

A RAW-edited photo often carries 50-200 KB of EXIF data plus an embedded thumbnail. Most browser compressors strip this by default. If your file is mysteriously stuck just above 100 KB:

1. Run it through /exif to view what metadata is present
2. Use the same tool's "strip metadata" mode to remove EXIF, color profile, and thumbnail
3. Re-check the file size — often you'll see 30-150 KB drop

Step 5: Verify and Iterate

Download the result and check the file size in your OS file manager. If still over 100 KB:

• Was the original a JPG? You wasted a step — JPG compresses better than PNG by default
• Is the image full of text? Try resizing smaller before recompressing
• Is it a screenshot of a UI with gradients? AVIF will beat WebP here, often by 30%

If you're under 100 KB but the image looks bad, go back to Step 2 and reduce dimensions further so you can raise the quality setting.

A Real Example

We started with screenshot.png — a 3,124 KB screenshot of a dashboard with gradients, text, and chart axes. Goal: under 100 KB.

Four decisions, total time under a minute, no upload needed.

The TL;DR

For PNG to fit under 100 KB:

1. Convert to WebP (transparency-safe, broadly supported)
2. Resize to actual display dimensions (1600 px is enough for most web)
3. Compress at quality 75 to start
4. Strip metadata if you're stuck just over the limit
5. Verify the final size and iterate quality 10 points at a time

Try it now with your own files at paste-to-download.com/compress — paste, drag, or pick files. Browser-local, no upload, no signup.