JPG to PNG Converter

What does a JPG to PNG converter do?

A JPG to PNG converter takes a JPG or JPEG photo and saves the same pixels in the PNG format. PNG uses lossless compression, which means that once your image is a PNG, you can edit it, crop it, add text to it and save it again as many times as you like without the quality slowly getting worse – something that happens every time a JPG is re-saved. This free MavexTech JPG to PNG converter works on a whole batch of files, keeps the exact pixel dimensions, and runs completely inside your browser, so the photos never leave your computer or phone.

People usually need JPG to PNG when a design tool, website builder, game engine or upload form asks for PNG, when they plan to edit an image several times, or when they want to add a transparent background later in an editor.

How to convert JPG to PNG

1. Add your images. Click the upload box or drag one or more .jpg or .jpeg files onto it.
2. Wait a moment. Conversion starts on its own. A counter on the button shows progress for large batches.
3. Review each file. Every row shows the new PNG name, the width × height in pixels and the size before and after.
4. Download one file with the button on its row, or download everything with Download all or as a single ZIP archive.
5. Start again with Clear when you want to convert a new set.

How it works

A JPG file stores a compressed approximation of the photo. Your browser decodes it into a grid of red, green and blue values – for a 3000 × 2000 photo that is 6,000,000 pixels. The tool draws that grid onto a canvas of exactly the same size and asks the browser to encode it as PNG. PNG stores every pixel exactly, using filtering and DEFLATE compression (the same family of compression used in ZIP files). Nothing is resampled, sharpened or smoothed, so the PNG is a pixel-for-pixel copy of the decoded JPG. In our tests, comparing the PNG output with the same JPG decoded independently gave an average difference of well under one level on the 0–255 scale, which is just normal rounding between JPEG decoders.

Why the PNG is bigger. JPG throws away fine detail to save space; PNG keeps everything, including the tiny compression noise that JPG introduced. So a photo almost always grows when converted. As a rough guide, the uncompressed size of an image is width × height × 3 bytes: 3000 × 2000 × 3 = 18,000,000 bytes (about 17.2 MB). A PNG of a busy, grainy photo can be close to that figure or even slightly above it, while a flat graphic or screenshot compresses far better. The size column on each result row shows the exact change for your file.

Converting to PNG cannot restore detail that the JPG already lost. It simply stops any further loss from that point on.

Use cases

• Editing in several steps: convert once, then crop, annotate and re-save as often as needed without generational JPEG loss.
• Design and presentation tools that prefer PNG for crisp layering, or where you plan to remove the background later.
• Screenshots or scanned text received as JPG, before you add arrows, highlights or captions.
• Developers who need PNG sprites or textures, or a PNG to turn into a data URI with our Image to Base64 tool.
• Forms that only accept PNG uploads.

Tips

• Only convert to PNG if you need it. For sharing photos online, JPG is smaller and loads faster.
• Resize before converting if the image is larger than you need – halving width and height cuts the number of pixels to a quarter. Use the Image Resizer or Image Crop.
• Phone photos are shown upright: the browser applies the camera's rotation flag, so the PNG is saved the way the photo looks on screen.
• If Download all saves only one file, your browser is blocking multiple downloads. Allow them for the site or use the ZIP button.

Limitations and notes

The converter does not make the background transparent; it copies the photo exactly, background included. CMYK JPGs from print workflows are converted to RGB by the browser, and embedded colour profiles and EXIF metadata (camera model, GPS, date) are not copied into the PNG – which can be useful for privacy. Extremely large photos may exceed the canvas limit of your browser, in which case that file is reported as an error. The ZIP option loads the JSZip library from the cdnjs CDN when first used; zipping happens on your device.

Frequently asked questions

Does converting JPG to PNG improve image quality?

No. PNG is lossless, so it preserves the pixels exactly as they are, but it cannot bring back detail that JPG compression already removed. It only prevents further quality loss when you edit and re-save.

Why is the PNG file larger than my JPG?

JPG discards detail to save space, while PNG stores every pixel exactly. Photos therefore usually become several times larger as PNG. Screenshots and simple graphics grow much less.

Will the PNG have a transparent background?

No. The converter keeps the photo exactly as it is, including its background. To get transparency you need to remove the background in an image editor after converting.

Are my photos uploaded anywhere?

No. The conversion runs in your browser on your own device. The files are not sent to MavexTech or any other server.

Can I convert JPEG files as well as JPG?

Yes. JPG and JPEG are the same format with different file extensions. Both are accepted and the output is saved with a .png extension.

Does the PNG keep the same dimensions?

Yes. Width and height in pixels are identical to the original photo as displayed, including the correct rotation for phone photos.

Related tools

• PNG to JPG – go back to a smaller JPG when you are done editing.
• Image Format Converter – PNG, JPG and WEBP in one place.
• WEBP to JPG – with an option to save WEBP as PNG.
• Image Resizer – change pixel dimensions.
• Image to Base64 – embed the PNG in code.