How to compress an image online
Image Compress Pro is an online image compressor for photos and graphics. Image compression reduces file size so a picture is easier to store, share, or add to a website. The right settings depend on the image: photographs often work well with JPEG, WebP, or AVIF, while diagrams and images with transparent backgrounds may need PNG or lossless WebP. There is no fixed reduction amount because source detail, dimensions, format, and quality settings all matter.
- Add your images using the upload area, or drag and drop them onto the page.
- Choose an output format. Use JPEG for widely compatible photos, PNG for transparent graphics, or WebP for modern websites.
- Open Edit and select Compress to adjust Quality. If needed, reduce the width or height. Compare the output preview and file size with the original.
- Download the optimized image, or compress images in a batch and download completed results as a ZIP.
JPEG, PNG, WebP or AVIF: choose the right image format
| Format | Often useful for | Trade-off |
|---|---|---|
| JPEG | Photographs and broad compatibility | Lossy; does not preserve transparency |
| PNG | Transparency, UI graphics, and sharp edges | Can be larger for detailed photographs |
| WebP | Modern websites and mixed image content | Some older software may not support it |
| AVIF | Smaller files in compatible browsers and apps | Compatibility is less universal than JPEG |
JPEG compressor for JPG photos
JPG and JPEG are the same format. To compress JPG files, choose JPEG output and start with a moderate quality setting. Inspect faces, text and fine detail before lowering quality further. JPEG works well for photographs but does not preserve transparent backgrounds.
PNG compressor for graphics and transparency
Keep PNG for logos, screenshots and graphics that need transparency. To compress PNG images, reducing unnecessary pixel dimensions can help; changing a quality slider alone does not control PNG output like it does JPEG. An already optimized PNG may not get smaller. If your destination accepts WebP, compare a WebP version as well.
WebP compressor for website images
To compress WebP images, select WebP output and adjust quality or dimensions. It can be a useful balance of file size and visual quality for product photos and web graphics. Check that the website, application or upload form you use accepts WebP files.
AVIF compressor compatibility
AVIF can store detailed images efficiently, but decoding and exporting support depend on your browser. To compress AVIF images in a compatible browser, try resizing and compare the result. Reading AVIF does not always mean a browser can encode AVIF output; choose JPEG or WebP if AVIF export is not supported, and check the format your destination requires.
Photo compressor and size reducer: pixels vs file size
If you need to reduce photo size for an email attachment, online form or product listing, first check whether the limit is in KB/MB or in pixels. An image size reducer lowers the bytes in a file; resizing changes its width and height. You may need both to meet an upload limit.
For example, a 4000 × 3000 photo resized to 1600 × 1200 contains fewer pixels while keeping the same proportions. Then choose a suitable format and quality to reduce image size further. Always compare the resulting file size and preview: savings vary, and repeated lossy compression can remove detail. Keep the original photo for editing or printing.
How to reduce an image to a 100 KB or 200 KB upload limit
Online forms can require both a maximum file size and specific image dimensions. Follow the form's rules rather than choosing the smallest file possible: a very small image may be unreadable or rejected.
- Check the accepted formats, maximum KB size, and required width and height before adding your photo.
- Choose JPEG for a photo when the form accepts it. Use PNG when transparency is required, or WebP only when the destination supports WebP uploads.
- Set the image dimensions to the form's requirements. Keep the aspect ratio locked; if the shape must change, crop in Edit instead of stretching the photo.
- Open Edit, select Compress, and enable Compress to target size. Choose the 100 KB or 200 KB preset. For manual JPEG or WebP quality control, turn target-size mode off and lower Quality gradually instead.
- Compare the preview and resulting file size. If the file is still above the limit, try smaller dimensions only when the form permits them. Download the result and check its size, format, and readability before submitting.
No setting guarantees an exact 100 KB or 200 KB result for every photo. PNG file size usually benefits more from reducing dimensions than from changing quality. Keep the original file and adjust settings from it rather than repeatedly uploading an already compressed download.
Resize images online with an image resizer
Use the online image resizer above when a website asks for a particular width or height. Add a photo, enter your target dimensions, and keep the aspect-ratio lock enabled to avoid stretching. For a different shape, crop the photo in the editor rather than distorting it. Check the preview before downloading your resized image.
Image resize settings for screens and print
Pixel dimensions describe how many pixels make up an image. Resizing to fewer pixels can reduce the file size, but enlarging an image cannot create missing detail. DPI describes print density: changing DPI changes how pixel dimensions map to a physical print size, not the number of pixels stored in the image.
Image compressor questions
What is an image compressor?
An image compressor reduces the bytes used to store a picture. Lossy formats can trade a little visual detail for a smaller file, while lossless formats preserve the original pixel data.
How do I reduce an image file size?
Add an image, choose an output format and quality, and download the result. For more control, resize its pixel dimensions before saving. The amount saved depends on the source image and settings.
Can I compress multiple images at once?
Yes. Add up to 10 images at a time. Each file can be up to 20 MB, with a 50 MB total file-size limit and 60 million combined pixels. Download completed files one by one or together as a ZIP.
Can I resize an image by pixels or print size?
Yes. Set width and height in pixels, inches, centimeters, or millimeters. Physical units are converted to pixels using the selected DPI.
What is the difference between JPEG, PNG, WebP, and AVIF?
JPEG is widely supported for photographs. PNG keeps sharp edges and transparency without lossy compression. WebP supports lossy and lossless images with broad modern-browser support. AVIF can produce small files, but some older apps may not open it.
What DPI should I use?
DPI affects the print-size conversion, not the number of pixels shown on a screen. For print, follow the printer or publisher's requirements; 300 DPI is a common print target. For screens, pixel dimensions matter most.
Are my images uploaded or stored?
The image files are processed in your browser and are not uploaded to our API. Background removal downloads model files from its asset host on first use; the image itself stays on your device.
Can I use the image compressor on a phone?
Yes. The page works in modern mobile browsers. Processing large images can use significant memory, so smaller batches are recommended on older or low-memory devices.
Can I compress an image without losing quality?
Lossless output can preserve pixel data when the selected format and browser support it. For lossy formats, use a higher quality setting and compare the preview; no lossy compression can guarantee zero visual change.
Is a JPG compressor different from a JPEG compressor?
No. JPG and JPEG are two filename extensions for the same image format. Choose JPEG output to compress JPG photos, then compare the quality and file size before downloading.
Can I compress an image to 100 KB or 200 KB?
Open Edit, select Compress, enable Compress to target size, and choose the 100 KB or 200 KB preset. Compare the resulting file size with your upload limit and inspect the preview. The target is best-effort, not guaranteed; if the result is still too large, try smaller dimensions when the upload rules allow them.
Why is my compressed image sometimes larger?
An already optimized image may not get smaller when re-encoded. Converting a photo to PNG or increasing dimensions can also increase file size. Compare the original and output sizes, try a smaller width or a different format, and keep the original if it is better.
For more detail about local processing and file limits, read about Image Compress Pro.