Image Compressor
Compress one or multiple JPG, PNG, and WEBP images locally in your browser. Files are processed without being uploaded to a server.
Drag and drop one or more images here, or choose files
Supported formats: JPG, PNG, WEBP
Compression Settings
Lower values reduce file size more, but may also reduce image quality.
If set, the image will be resized based on its longest side.
Download compressed files separately through your browser.
Original Files (0)
Compressed Results (0)
About this image compressor
This tool helps you reduce image file size directly in your browser. It supports both single-image and batch compression workflows.
You can compress by manual quality settings or use a target file size in KB for more practical workflows such as form uploads or blog publishing.
Files can be downloaded one by one or together as a ZIP file after compression.
FAQ
Can I compress multiple images at once?
Yes. You can upload multiple files and compress them together with the same settings.
Can I compress an image to 100 KB or 200 KB?
Yes. Use target file size mode and enter the size you want in KB. The tool will try to reach that size as closely as possible.
Why is my PNG file not getting much smaller?
PNG is often used for lossless images, graphics, and transparent files. Some PNG images are already well optimized, so additional compression may have limited effect.
How Image Compression Works
This tool uses the browser-image-compression library to reduce file size without leaving your device. When you select an image, the library analyzes the pixel data and applies lossy or lossless compression algorithms entirely within the JavaScript runtime. For JPEG images, it adjusts the quantization tables that control how finely color gradients are encoded, discarding imperceptible detail to shrink the byte count. For PNG, it recompresses the deflate stream at a higher effort level, squeezing out redundancy without altering any pixel values.
Because the entire process happens inside your browser tab, your original files are never transmitted to a server. The compressed output is generated as a Blob in memory and offered as a direct download through an object URL. This means compression is fast, private, and works even without an internet connection after the page has loaded. The algorithm automatically caps output dimensions when you set a maximum megapixel limit, which prevents accidental upscaling artifacts while still honoring your chosen quality target.
When to Use the Image Compressor
- 1Reducing hero images and product photos before uploading to a CMS or e-commerce platform — large images slow page load times and hurt Core Web Vitals scores.
- 2Shrinking email attachments so they pass through corporate mail servers that enforce a 10 MB or 25 MB limit per message.
- 3Preparing images for social media platforms such as Instagram, Twitter, or LinkedIn, which re-compress uploads and benefit from pre-optimized source files.
- 4Archiving large photo libraries where storage costs matter — compressing a folder of vacation JPEGs from 20 MB each down to 3–4 MB can save gigabytes with minimal visible quality loss.
Quality vs. File Size Guide
Quality 80–90 %: The sweet spot for photographs. The human eye rarely detects the difference between quality 90 and 100, yet file size often drops by 50–70 %. Use this range for blog images, portfolio pages, and product listings.
Quality 60–75 %: Good for thumbnails, preview images, and background decorations where the viewer is not studying fine detail. Savings of 75–85 % are common at this range.
Quality 40–55 %: Suitable for low-bandwidth use cases such as chat thumbnails, email previews, and icon-sized references. Noticeable compression artifacts may appear on edges and gradients.
For PNG images, prefer lossless mode when transparency is required. Lossy PNG compression may introduce fringing around transparent edges that is difficult to remove later.
Supported Formats & Browser Compatibility
- Supported input formats: JPEG (.jpg, .jpeg), PNG (.png), WebP (.webp), and GIF (.gif, single frame).
- Output format mirrors the input by default; you can optionally force output to JPEG for the smallest file size.
- Browser support: Chrome 90+, Edge 90+, Firefox 88+, Safari 15+. WebP input requires Safari 14 or later. All modern mobile browsers are supported.
- File size limit: the tool handles files up to approximately 50 MB in a single pass; larger files may cause memory pressure on low-RAM devices.
Tips for Best Results
Tip 1
Start with quality 80 and compare the preview before going lower — most photographs look identical at quality 80 versus 100.
Tip 2
Enable the 'maximum width' option for images wider than 1920 px; most screens cannot display the extra pixels, and the size saving is dramatic.
Tip 3
Compress PNG screenshots as JPEG if the image contains no transparency — screenshots are often 5–10× smaller as JPEG.
Tip 4
Batch-process a folder by selecting multiple files at once; each file is compressed independently so you get per-file savings reports.
Tip 5
If you need the smallest possible file for a web hero image, try WEBP output — it typically beats JPEG by an additional 25–35 % at the same perceived quality.
Tip 6
Always keep your original file. Repeated re-compression (compress → edit → compress again) causes generational quality loss that accumulates quickly.
Help
Frequently Asked Questions
Does this tool upload my images to a server?
No. All compression happens inside your browser using JavaScript. Your images never leave your device and are not sent to any server.
What quality setting should I use for a website?
Quality 80 is a reliable default for most web images. It cuts file size dramatically with negligible visible degradation. For hero images or portfolio work where quality matters most, try quality 85–90.
Why is the compressed file sometimes larger than the original?
This can happen with very small files or images that were already heavily compressed. Re-compressing a JPEG that was saved at quality 70 at quality 80 adds data without removing it. In this case, keep the original.
Can I compress PNG files without losing transparency?
Yes. When you compress a PNG, the tool preserves the alpha channel (transparency). Use lossless mode or a high quality setting (85+) to avoid fringing artifacts around transparent edges.
How many files can I compress at once?
You can process multiple files in a single batch. The tool compresses them sequentially and lets you download each result individually or as a ZIP archive.
Does compression work on mobile browsers?
Yes, on all modern mobile browsers including Mobile Chrome and Mobile Safari. Performance depends on your device's RAM — very large files (>20 MB) may be slow on older phones.
What is the difference between lossy and lossless compression?
Lossy compression permanently discards some image data to achieve smaller files, which is ideal for photographs. Lossless compression reorganizes the data for a smaller file without discarding anything, which is ideal for screenshots, logos, and graphics with flat colors.
Will compressed images look different on retina screens?
At quality 80 or above, the difference is imperceptible on retina displays for most photographic content. If you are targeting retina screens specifically, use quality 85–90 to be safe.