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Image Compressor – Reduce Image Size in KB Online

Make JPG, PNG and WEBP photos smaller — by choosing a quality or by typing the exact size in KB you need. Compress up to 20 photos at once; they never leave your device.

Your files stay on your device

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How to use the image compressor

  1. Choose a mode: By quality (pick a quality from 10% to 95%) or Target size (KB) (type the size you need).
  2. Optional: pick an output format and a maximum width/height — shrinking huge phone photos saves the most space.
  3. Add your images — choose files, drop them on the box, or paste a screenshot with Ctrl/⌘ + V.
  4. Each image is compressed straight away. You’ll see the old and new size and the saving.
  5. Tap Save for one image or Download all (ZIP). Changed a setting? Tap Re-compress all.

How image compression works

A photo from a modern phone is often 3,000–4,000 pixels wide and 2–5 MB. Most of that detail isn’t needed for a form, an email or WhatsApp. The compressor uses two techniques:

  • Quality (JPG and WEBP). These formats store the picture in small blocks and throw away fine detail your eyes are least sensitive to. Lower quality means smaller files.
  • Dimensions. Fewer pixels means a smaller file. A 4,000-pixel photo shrunk to 1,920 pixels has about a quarter of the pixels.

Exact target size

In Target size mode, the tool repeatedly tries different quality levels (a binary search) to find the highest quality that fits under your limit. Only if even the lowest quality is too big does it reduce the dimensions. So you get the best-looking photo that still meets the size rule.

Example

A 3.6 MB phone photo at 75% quality often comes out between 300 and 600 KB — over 80% smaller — and looks the same on screen. With a target of 100 KB, it fits the limit with a little more softness that’s hard to notice on a phone.

Tips for the best results

  • Start from the original photo, not a WhatsApp-forwarded copy — those are already compressed.
  • Crop first to remove what you don’t need; a smaller area compresses better. Use crop image.
  • For exam or job forms that need exact pixel sizes as well as KB limits, use the photo & signature resizer instead.
  • Keep a copy of the original. Compression can’t be undone.

Who uses an image compressor

  • Students and job seekers uploading photos and documents with KB limits.
  • Online sellers making product photos load faster.
  • Bloggers and website owners speeding up their pages.
  • Anyone emailing photos when attachments are too large.

To change the size in pixels or centimetres instead, try the image resizer. To put photos into a single PDF, use JPG to PDF.

Frequently asked questions

How do I reduce a photo to 50 KB or 100 KB?

Choose “Target size (KB)”, type 50 (or 100) and add your photo. The tool finds the highest quality that stays under that size, and only reduces the dimensions if quality alone isn’t enough.

Will compressing reduce the quality of my photo?

JPG and WEBP compression removes detail your eyes barely notice. At 60–80% quality most photos look the same as the original on a phone or laptop. Very small targets, like 20 KB for a large photo, will show some softness.

Are my photos uploaded to a server?

No. Everything happens inside your browser on your own phone or computer. Your photos are never uploaded, so they stay private — you can even turn off the internet after the page loads.

Why didn’t my PNG get much smaller?

PNG is a lossless format, so it can’t be compressed much without changing format. For big savings, choose JPG (for photos) or WEBP (which also keeps transparency) as the output format.

What is the difference between KB and MB?

1 MB = 1,024 KB. A typical phone photo is 2–5 MB (2,000–5,000 KB). Online forms usually mean 1 KB = 1,024 bytes, which is how this tool measures size.

Can I compress many photos at once?

Yes — add up to 20 images. Each one shows its new size and the percentage saved, and you can download them one by one or all together as a ZIP file.

Which output format should I choose?

JPG for photos and anything you upload to forms, WEBP for websites (smaller, keeps transparency), and PNG for screenshots or graphics where every pixel must stay exact. “Same as original” keeps the format you uploaded.

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