Original Image
ORIGINAL
No image has been uploaded yet.
Image Utility
Image Format Converter
Convert JPG, PNG, and WEBP images while adjusting dimensions, quality, and transparency. Everything is processed in your browser without uploading files to a server.
Private Browser Processing
Process images directly in your current browser without sending or storing them on a server.
Format and Resize
Convert between JPG, PNG, and WEBP while setting output dimensions and image quality.
Compare Results Clearly
Review file size, dimensions, and the percentage change before downloading the result.
STEP 1
Upload an Image
Choose one JPG, PNG, or WEBP image to convert.
Privacy
Your image is never sent over the network. The converted file is newly generated and does not include the original EXIF or location metadata.
STEP 2
Conversion Settings
Adjust the output format and dimensions, then compare the original image with the result.
Converted Result
RESULT
The converted result will appear here.
Original Size
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Result Size
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Size Change
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Output Dimensions
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Upload an image, then choose your conversion settings.
Choose between JPG, PNG and WebP before converting
Choose the format accepted by the destination and the properties you need to keep. Photos, transparent logos and screenshots can benefit from different settings. A conversion can make a file larger, so check the actual result.
Who this helps
- People converting a screenshot or photo for an upload form.
- People preparing transparent graphics for a website.
When to use this tool
- Convert PNG to JPG when a form accepts JPEG only.
- Compare JPG and WebP for a photo, or keep alpha with PNG/WebP.
From input to a checked result
- 1
Select a JPEG, PNG or WebP file. The input limit is 40 MiB; images and output are limited to 40 million pixels and 12,000 pixels per side.
- 2
Select the destination format: JPEG for a flat background, PNG for lossless pixel encoding, or WebP for an alternative size/quality tradeoff.
- 3
Keep the aspect ratio while changing dimensions. For JPEG, choose the background that will replace transparent areas.
- 4
Adjust JPEG/WebP quality, convert, then compare the preview, actual format, dimensions and bytes.
- 5
Download and open the file in the app or form where it will be used.
A photo for the web
- Input
- 2400×1600 JPEG; WebP quality 85; width 1200 with ratio locked
- Result
- 1200×800 WebP when supported by the browser.
This is a dimension example, not a measured file-size promise. Compare text, edges and actual bytes.
Transparent artwork for a JPEG-only form
- Input
- Transparent PNG; JPEG output; white background
- Result
- Transparent areas are filled with white.
JPEG has no alpha channel. Retain the original PNG if you will need transparency later.
How it works
The selected file is decoded and drawn to a browser canvas. The canvas is exported with the chosen MIME type, and the tool checks the actual format returned by the browser. JPEG/WebP quality ranges from 0.1 to 1.0 internally; PNG does not use that quality setting.
Limitations
- Converting JPEG to PNG cannot restore detail lost in earlier JPEG compression.
- Output bytes vary with the browser encoder and the original's compression.
- Animated WebP becomes a still image. EXIF is not copied, and color profiles may differ.
- HEIC is not accepted here; use a dedicated HEIC converter and check its processing policy.
Your data
The image is processed locally in your browser without uploading it to the win-j server or saving it in localStorage. The original file is unchanged.
References
Related tools
- Image Compressor
Reduce unnecessary width and compare quality when upload size is the problem.
- Image Resizer
Prepare the dimensions requested by the destination.
Frequently asked questions
Does JPG to PNG improve quality?
No. It changes how the decoded pixels are stored and may increase file size. Missing detail is not recovered.
Which format keeps a transparent background?
PNG and WebP support transparency in this tool. JPEG replaces it with the selected background.
Is WebP always the smallest?
No. A small, already optimized PNG or WebP can grow after re-encoding. Compare the result with the original.
Is my original image overwritten?
No. Downloading creates a separate result. Keep the original for future edits.