Free Bulk Image Resizer Online — Resize JPG, PNG, WebP & AVIF
Resize images by exact pixels, maximum width or height, longest edge, percentage, social media presets, or a maximum file size such as 100 KB. Smart Quality helps stop a smaller JPEG from unexpectedly becoming a larger file, while crop position, background color, rotation and flip controls give you cleaner output without opening a photo editor.
A useful image resizer should do more than make a picture smaller. Sometimes you need an exact 1200×630 canvas, sometimes every photo must fit within a 1600-pixel longest edge, and sometimes the only requirement is to keep an upload under 100 KB or 200 KB. This free browser-based image resizer handles those jobs in one place. It supports JPEG-family files including JPG, JPEG, JFIF, JPE, PJPEG and PJP, plus PNG, WebP, AVIF, GIF and BMP as still images. You can resize a single image or batch resize up to 20 files, preview the result, then download each file or a ZIP.
📷 Advanced Bulk Image Resizer
Pixels · Max Width/Height · Longest Edge · Percentage · Presets · Target KB · Smart Quality
🔒 Local file workflow: selected images are processed in your browser for resizing and are not intentionally uploaded to an MZ Tech Pro file-processing server. The webpage itself may still make normal network requests for required page assets and any enabled analytics, consent or advertising services. A ZIP helper is fetched only if you request a multi-file ZIP download.
How to Resize Images Online
- Add one image or a batch. Choose files, drag them onto the upload area, or paste a copied screenshot. You can batch resize up to 20 images at once.
- Choose the resize method. Use Width × Height for an exact box, Maximum Width or Maximum Height for responsive web images, Longest Edge for mixed portrait/landscape photos, Percentage for proportional scaling, Presets for common canvases, or Target KB for a file-size ceiling.
- Control the fit. Fit keeps the whole picture. Fill & Crop creates an exact canvas and lets you choose where the crop is anchored. Stretch forces exact dimensions and can change the image's proportions.
- Choose format and quality. Export JPG, PNG or WebP. Leave Smart Quality enabled when resizing JPEG/JFIF-family photos so a smaller image does not unnecessarily become a larger file.
- Resize, compare and download. The result shows output dimensions, file size, format, quality used and the percentage size change. Download files individually or save a multi-image batch as a ZIP.
Image Resizer Features
🧠 Smart JPEG Quality
A smaller JPEG can become a larger file after re-encoding. Smart Quality compares the new JPEG/WebP with the original and lowers export quality only when necessary, aiming for the highest quality that does not exceed the original file size.
📏 Max Width, Height & Longest Edge
Resize mixed images without calculating each dimension yourself. Set a maximum width for website uploads, a maximum height for portrait assets, or one longest-edge value for an entire photo batch.
💾 Resize Image to 100KB or Another Limit
Set a maximum size in KB or MB. The tool optimizes JPEG/WebP quality first and can then reduce dimensions proportionally until it gets at or below the requested limit when technically possible.
📦 Bulk / Batch Image Resizer
Resize up to 20 JPG, PNG, WebP, AVIF and other supported still images with the same settings, then download each result or create one ZIP.
✂️ Crop Position Control
Fill & Crop no longer has to be center-only. Anchor the crop to the top, bottom, left, right or a corner so faces, products and text are less likely to be cut off.
🔄 Rotate, Flip & Convert
Rotate by 90°, 180° or 270°, flip horizontally or vertically, and export to JPG, PNG or WebP during the same resize operation.
🚫 Do Not Enlarge
Prevent accidental upscaling. Fit, percentage, maximum width/height and longest-edge modes stay within the source size, while exact presets or Fill/Stretch settings that need enlargement are blocked until you explicitly allow it.
📋 Paste Screenshots
Paste an image directly from the clipboard with Ctrl+V or Cmd+V. It enters the same local resize workflow as a file selected from your device.
Resize Image Dimensions Without Unnecessary File-Size Growth
Image dimensions and image file size are related, but they are not the same thing. A 2000×1500 JPEG may already have been saved with aggressive compression. If it is resized to 1200×900 and then re-encoded at a higher JPEG quality, the new file can be larger even though it contains fewer pixels. That is why a simple fixed-quality image resizer can give surprising results.
Smart Quality treats your selected quality as a maximum rather than a rule that must always be used. For a JPEG-family source that is not being enlarged, the resizer first produces the requested dimensions. If the encoded JPEG or WebP is larger than the original, it searches downward for the best quality that fits within the original byte size. This makes the normal resizing workflow more sensible without turning it into an aggressive compressor. If your main goal is maximum file-size reduction while keeping the same dimensions, use the Image Compressor instead.
Resize JPG, JPEG, JFIF, PNG, WebP, AVIF, GIF & BMP
The input list is broader than the output list because browser support for reading and exporting image formats is not identical. The tool handles that difference explicitly rather than giving a file the wrong extension.
| Format | Input | Output | Notes |
|---|---|---|---|
| JPG / JPEG / JFIF / JPE / PJPEG / PJP | ✅ Yes | ✅ JPG | All JPEG-family extensions are normalized to standard .jpg on export. |
| PNG | ✅ Yes | ✅ PNG | Transparency is retained when exporting PNG/WebP. |
| WebP | ✅ Yes | ✅ WebP | Useful when you want compact web-ready output. |
| AVIF | ✅ Browser-dependent decode | Convert to JPG/PNG/WebP | AVIF input works where the browser can decode it; native AVIF export is intentionally not promised. |
| GIF | ✅ Still frame | Convert to JPG/PNG/WebP | Animated frames are not preserved. A dedicated animated GIF resizer is a separate workflow. |
| BMP | ✅ Yes | Convert to JPG/PNG/WebP | “Keep original” falls back to PNG because native BMP export is not offered by this tool. |
Pixels, Percentage, Longest Edge, Presets or Target KB?
Width × Height
Use a size box when a website, ecommerce listing or design calls for specific dimensions. Fit keeps the entire image; Fill & Crop makes the requested exact canvas; Stretch changes the aspect ratio.
Max Width / Height
Set only the dimension that matters and let the other side stay proportional. “Do not enlarge” prevents small source images from being scaled up unnecessarily.
Longest Edge
A portrait and a landscape image can both be limited to a 1600 px longest edge without separate calculations. Their individual aspect ratios remain unchanged.
Target KB / MB
Use a maximum such as 100 KB, 200 KB, 500 KB or 1 MB when the receiving site cares more about file size than exact dimensions. The tool may lower quality and then dimensions to reach the cap.
When a Bulk Photo Resizer Saves Time
Why Is My Resized Image Larger Than the Original?
JPEG became larger after resizing
Leave Smart Quality enabled. A highly compressed original JPEG can be smaller than a fresh 85% export. The tool now adjusts JPEG/WebP quality only when the resized output would otherwise exceed the original size.
PNG is still large
PNG is lossless, so its quality cannot be lowered like JPEG. Reduce dimensions further or export to WebP/JPG when transparency or lossless output is not required.
The preset cuts off important content
Use Fill & Crop with a different Crop Position, or switch to Fit if keeping the entire image matters more than filling an exact canvas.
AVIF will not open
AVIF decoding depends on the browser. If a particular browser cannot decode the file, open the tool in a current browser that supports AVIF or convert the image first.
Image Resizer Questions
- Yes. Add up to 20 supported images, choose one set of settings, resize the batch and download the results individually or as a ZIP.
- Choose Target KB, enter 100 or 200, select KB and resize. For JPG/WebP the tool searches for a suitable quality first; if needed it also reduces dimensions. The result is treated as a maximum target, so it can be smaller than the number you entered. If the original already fits the target and you are keeping its supported source format without rotation or flipping, the tool can keep the original file unchanged.
- The original JPEG may already use stronger compression than the new export. Fewer pixels do not guarantee fewer bytes. Smart Quality compares the resized JPEG/WebP with the original and lowers export quality only if necessary when the source is a JPEG-family file and is not being enlarged.
- The image files are processed in your browser and are not uploaded to MZ Tech Pro for resizing. If you request a multi-file ZIP, the ZIP is still created in your browser.
- JPEG-family extensions such as JFIF, JPE, PJPEG and PJP are supported and export as standard JPG. AVIF can be used as an input when your browser can decode it, then exported as JPG, PNG or WebP.
- No. GIF input is treated as a still image, so animation is not preserved. Animated GIF resizing requires a separate animation-aware workflow.
- Use Fit, Maximum Width, Maximum Height, Longest Edge or Percentage. These methods preserve the image's aspect ratio. Stretch should only be used when exact dimensions matter more than maintaining proportions.
- JPG is a practical choice for photographs, PNG is useful when you need lossless output or transparency, and WebP is useful for compact web images. The best format depends on the image and where you plan to use it.
- Not reliably. Resized files are newly encoded images, so EXIF/IPTC metadata such as camera details, captions and location tags may be removed. Keep the original file if you need that metadata.
Resize a Photo or a Full Batch Now
Choose the dimensions or file-size limit you actually need, keep Smart Quality on for JPEG photos, and download the finished images directly from your browser.
📷 Open Image Resizer