Image Compressor

What is Image Compressor?

Free online image compressor. Compress JPEG, PNG, WebP images to reduce file size without visible quality loss. Works in your browser, no upload needed. Browser-based image tools — no upload to servers, all processing done locally. TekPulse's Image Compressor is completely free — no signup, no ads in results, and no data stored on our servers.

How to Use Image Compressor Online

1. Upload one or more images (JPG, PNG, or WebP) using the drop zone
2. Adjust the quality slider (recommended 70–85% for a good size/quality balance)
3. View the before and after file sizes and the compression percentage achieved
4. Download individual compressed images or all as a ZIP
5. All compression happens in your browser — no files are ever uploaded to a server

Image Compressor Formula & Calculation

JPEG and WebP use lossy compression: the 'quality' setting controls how aggressively the encoder quantizes (simplifies) color and detail information before encoding — higher quality preserves more fine detail at a larger file size, lower quality discards more detail (especially in busy/textured areas, which the human eye is less sensitive to) for a smaller file. This tool draws your image onto a canvas and calls canvas.toBlob() with the chosen MIME type and a quality value between 0 and 1, which hands off the actual compression work to the browser's native image encoder. PNG, by contrast, is always lossless — it compresses the exact pixel data without discarding anything, which is why the quality slider doesn't shrink PNG output the way it does JPEG/WebP.

Example: A 2.4MB photo compressed as JPEG at 80% quality might shrink to ~380KB — a reduction of (2400−380)/2400×100 ≈ 84% — with the quality loss barely visible on screen, because JPEG's compression algorithm is tuned to discard information humans don't easily perceive.

Key Factors That Affect Your Result

1. Quality setting — Below ~60% quality, JPEG compression artifacts (blockiness, color banding) become visible, especially around sharp edges and text; 70–85% is the sweet spot for web use — small file, no visible quality loss to most viewers.
2. Output format — WebP typically achieves 25–35% smaller file sizes than JPEG at equivalent visual quality thanks to a more modern compression algorithm, but has historically had less universal support in older software (not a concern in modern browsers).
3. Image content — Photos with lots of fine detail/texture (foliage, fabric) compress less efficiently than images with large flat color areas (screenshots, illustrations) — the latter can often go to PNG for better results since PNG excels at flat colors.
4. Resolution vs. quality trade-off — For the same target file size, reducing the image's pixel dimensions (using the Image Resizer first) often preserves more perceived sharpness than keeping full resolution and cranking the compression quality down.

Why Use TekPulse Image Compressor?