Image Resizer and Compressor
Resize and compress images to reduce file size. Batch convert to JPEG, PNG, or WebP right in your browser.
Images are processed only within your browser. Files are not uploaded to the server, and the tool works offline. You can safely reduce personal photos or confidential material.
| File | Original Size | Converted Size | File Size | Saved | Action |
|---|
What is the Image Resizer and Compressor?
Modern photos are often too large for web use, slowing down your site and wasting visitor data. This tool lets you resize and compress images quickly. Drag and drop multiple files, set a new width or percentage, and convert to efficient formats like JPEG or WebP to drastically reduce file size. Best of all, every operation runs entirely within your browser. Your images are never uploaded to a server, ensuring your personal photos and confidential files remain private. It's free, with no sign-up needed.
How to use
- Drag & drop image files into the designated area or click to select them. You can process multiple images at once.
- Select a resize mode: `📐 Pixels` or `％ Percentage`. To maintain proportions, enter a new `Width (px)` and ensure "Keep aspect ratio" is checked.
- Choose a `Save format`. For photos, `WebP` offers the best compression. Adjust the `Quality` slider; around 80 is a good balance for size and quality.
- The results table updates instantly, showing new dimensions and file size savings. Click `Save` on any image or `⬇ Download All` to get the converted files.
Image Resizer and Compressor guide
How this tool is used in real work, and what to watch out for.
The Three Levers for Reducing File Size, Ranked by Effectiveness
There are three main ways to reduce an image's file size, but their impact is vastly different. Knowing the right order can save you a lot of wasted effort.
| Method | Effect | Quality Loss |
|---|---|---|
| Reduce dimensions (pixels) | Massive — Halving the width reduces the pixel count to a quarter (a 75% reduction). | None, if the original was larger than its final display size. |
| Convert to WebP | Large — Usually smaller than JPEG at the same visual quality. | Almost none. |
| Lower quality | Medium — Efficiency drops sharply below a quality setting of 80. | Becomes noticeable below 80. |
The Ideal Width Depends on Where the Image Will Be Used
You shouldn't guess the width. A good rule of thumb is to make it about twice the width it will actually occupy on the screen. The '2x' factor is for high-density (Retina) displays, common on modern phones and laptops, which use two physical pixels to render one CSS pixel.
| Use Case | Recommended Width | Notes |
|---|---|---|
| Blog post content | 1200px | The editor might resize it automatically, but pre-sizing speeds up uploads. |
| Wide blog themes | 1200–1600px | For themes with a wide content area. |
| E-commerce product details (long vertical images) | 860–1000px | Standard for most platforms like Shopify or WooCommerce. |
| Instagram square post | 1080×1080px | Instagram will downscale larger images to 1080px anyway. |
| Social media share preview (Open Graph) | 1200×630px | The aspect ratio must be correct, or the image will be cropped. |
| Full-width hero image | 1920px | 2560px is usually overkill. |
| Thumbnail or card view | 640px | Using a 1200px image for a small thumbnail is a waste of bandwidth. |
Why a Quality of 80 Is the Sweet Spot
The 'Quality' setting for JPEG and WebP isn't linear. Dropping from 100 to 90 causes a big drop in file size with almost no perceptible loss in image quality. The same is true from 90 to 80. Below 80, however, file size shrinks more slowly while quality degrades much faster. The 'knee' of this curve is typically between 75 and 85, which is why this tool defaults to 80.
However, this is based on photographs. The optimal value differs depending on the image type.
- Landscape and portrait photos: 80 is usually sufficient. It's difficult to tell the difference from the original with the naked eye.
- Images with text (product details, infographics): 90 or higher. At lower qualities, you'll see messy compression artifacts around the text.
- Graphics and logos with large areas of solid color: Don't use JPEG. It creates ghostly smudges at the edges of shapes. PNG or WebP is the right choice here.
- Screenshots: Use PNG. Text in a JPEG screenshot often looks blurry and smudged.
What Gets Lost During Conversion
This tool works by redrawing the image onto a canvas and creating a new file. In this process, all metadata from the original file is stripped. This has both good and bad consequences, and it's best to be aware of them.
- GPS location data: This is removed. That's a good thing. Photos from your phone often contain GPS coordinates, and uploading them directly to a blog could expose your home address.
- Photo metadata (EXIF): Camera model, aperture, shutter speed, and capture date are all gone. If you're archiving photos for professional use, keep the original files separately.
- Color profiles (ICC): These are removed. Photos taken in a wide color gamut (like Display P3) might look slightly washed out after conversion. Standard sRGB photos are unaffected.
- GIF animations: Only the first frame is kept, resulting in a static image. Do not use this tool for animated GIFs.
- Transparency + JPEG: Transparent areas are filled with white. The tool intentionally adds a white background to prevent transparent areas from turning black, but this can look awkward if the image is intended for a dark background. If you need transparency, choose PNG or WebP.
What If the File Size *Increases* After Conversion?
Sometimes, the savings rate will be negative. You'll see a red badge in the table like "+18%", and the status message below will change to a warning. There are a few common reasons for this.
- Re-compressing an already optimized image: Images downloaded from the web are often pre-compressed. Applying a 90 quality setting to such an image can actually increase its size. Try lowering the quality.
- Saving a photograph as a PNG: PNG is a poor choice for photos. The file will often be several times larger than the original JPEG. For photos, stick to WebP or JPEG.
- Very small images: If an image is already under 100 KB, there's not much room for further reduction.
- Changing format without changing dimensions: If you keep the original pixel dimensions, the effect will be limited. Reduce the width first for the biggest savings.
Frequently asked questions
Are my images uploaded to a server?
No. This tool processes all images directly in your browser. Your files never leave your device, so you can safely handle sensitive or personal photos.
What happens to images with transparent backgrounds?
To preserve transparency, save your image as a PNG or WebP. If you convert to JPEG, which doesn't support transparency, the background will become solid white.
Which save format is the best?
For web pages, `WebP (Recommended · Smallest size)` is ideal. For graphics that need transparency without any quality loss, use PNG. JPEG offers wide compatibility.
What does the `Quality` slider do?
It adjusts the compression for JPEG and WebP formats. A value around 80 offers a good balance of quality and file size. The slider is disabled for PNG because it's a lossless format.