Image Converter (JPG, PNG, WebP)

What converting does, and why renaming the file does not

Each job has a format that suits it: photographs in JPG, anything with a transparent background in PNG, images on a web page increasingly in WebP, which is usually the smallest of the three at a comparable quality. The trouble is that you rarely get to choose what you are handed. Phone cameras produce JPG or HEIC, macOS screenshots are PNG, and the upload form in front of you wants something else.

The most common mistake is renaming photo.png to photo.jpgand hoping. The extension is only a label. The bytes inside still start with the PNG signature, and any program that reads the header instead of the name will notice at once. That is where “this is supposed to be a JPG but it will not open” comes from, and why an upload form can reject a file that looks correct in your file manager.

A real conversion decodes the image back into pixels and encodes those pixels again in the target format, which is what this page does: the browser draws your image onto a canvas and exports it as JPG, PNG or WebP. Nothing is uploaded. Because it is a genuine re-encode, quality is a decision you cannot avoid. JPG and WebP are lossy, so the encoder needs a number telling it how much detail it may discard, which is what the slider under the format menu sets, at 90 by default. PNG is lossless, so the slider disappears when you pick it, and the pixel dimensions never change either way.

Which format, and which quality, for which job

Picking the output format:

• Images for a website: WebP. It has lossy and lossless modes, keeps transparency, and is the smallest of the three at a comparable quality, which helps your Largest Contentful Paint.
• Anything with a transparent background: PNG or WebP. JPG has no alpha channel, so transparency cannot be preserved, only filled in.
• Photographs where file size matters: JPG. Decades of tuning went into making its artifacts invisible on photographic detail.
• Screenshots, text, diagrams and line art: PNG. Lossy compression puts halos around hard edges, which is most of what a screenshot contains.
• Maximum compatibility with old software: JPG.

Conversions people actually come here for:

• HEIC to JPG or PNG: iPhone photos that Windows and many Android apps will not open. This depends on the browser being able to decode HEIC, which in practice means Safari on an Apple device. See the platform notes below.
• PNG to WebP: hero images and blog thumbnails, where a PNG exported from a design tool is often several times larger than it needs to be.
• Screenshot PNG to JPG: when an email attachment limit or a support portal is refusing the file for size.
• WebP to JPG or PNG: an image saved from a modern site that older desktop software or an office suite will not accept.
• A folder of mixed exports: everything normalized to one format in a single batch, downloaded as one ZIP.

Where to leave the quality slider: for photos and screenshots, 80 to 90 typically halves the file with no visible difference. Use 100 for an archive copy you intend to edit again. Below about 80, text, line art and large flat areas of color start to show noise around the edges, and for those PNG is a better answer than a lower quality number. The slider only re-runs the batch when you let go of it, so dragging stays smooth.

The three formats side by side

Convert one image, and shrink it while you are there

1. Choose the output format first. It applies to every file in the list, not one file at a time.
2. If you picked JPG or WebP, the quality slider appears underneath. Leave it at 90 unless you already know you want something else.
3. Drag the image into the dashed box, or use the file picker. On a phone, tapping it opens your photo library or file app.
4. Read the row that appears: original size on the left, target format in the middle, converted size on the right. The thumbnail is the converted result, so open it to check the quality.
5. Not happy? Move the slider. When you release it, the batch is converted again from the files you dropped in, so repeated adjustments never stack up compression damage.
6. Click the download icon on the row. The file keeps its original name with the new extension.

Convert a whole folder and take away one ZIP

1. Drag in the whole folder of images at once. The suggested limit is 50 files of up to 10 MB each; anything larger is skipped, and a message tells you how many were dropped and why.
2. A progress line shows how many are done. All of it runs on your own machine, so the speed depends on the device and the pixel dimensions, not on your connection.
3. The summary line then gives the total and the number converted. Anything that failed is marked in red with the reason on its own row; the usual cause is a format this browser cannot decode.
4. Check the format and quality are what you want, then press Download all as ZIP. Inside, each file keeps its original name with the new extension, and duplicate names get a numeric suffix so nothing is overwritten.
5. Press Clear to start over, or remove individual rows with the button at the end of each one.

Changing the format or the quality partway through does not mean picking the files again. The tool keeps the originals and re-runs the batch from them, so you can try three quality settings without ever converting a converted file.

Getting the converted images where they need to go

• One file: the download icon on its row. It lands in your browser’s download folder, named after the original.
• The whole batch: Download all as ZIP gives you an archive named after the site and the date. Windows has Extract All built in; macOS unpacks it on a double click.
• iPhone and iPad: Safari downloads go to the Downloads folder in the Files app, not to Photos. To put an image back in your library, open it in Files, share it and choose Save Image. Tapping a ZIP in Files expands it in place.
• Android: files usually land in the Download folder, which your file manager app opens.
• Into HTML, CSS or Markdown: a converted image can be inlined as a data URL instead of shipped as a separate request. See image to Base64.

Download before you close the tab. The results only exist in that page’s memory, so a reload throws them away, and no copy is kept anywhere else.

Where behavior differs by browser and platform

• HEIC needs a browser that can decode it. In practice that is Safari on an iPhone, iPad or Mac. Open this page in Chrome on Windows or Android and HEIC files will fail to read. This is a browser capability, not a restriction of this site. The reliable workaround is on the phone: Settings, Camera, Formats, Most Compatible captures JPG instead.
• WebP support is broad but not universal. Chrome, Firefox and Edge have supported it for years, and Safari added it in version 14, alongside iOS 14 in 2020. If a file has to open in much older software or an old office suite, choose JPG.
• Social and messaging apps re-encode what you upload. Most compress with their own settings, so the quality you choose here decides the file on your device, not necessarily what the recipient sees. Sending it as a file attachment rather than as a photo usually preserves more.
• Upload forms often accept JPG and PNG only. Bank, government and insurance portals tend to list the accepted types and a maximum size, and many still do not recognize WebP. Follow the form’s own stated rules, and convert to JPG when in doubt.
• Print work is a different pipeline. Commercial printers want CMYK at a print resolution, and a browser canvas outputs sRGB, so follow the file specification your printer publishes.

Limits worth knowing before you convert

• PNG to JPG: transparent areas are filled with white, because JPG has no alpha channel.
• JPG to PNG: the file usually gets larger, and the detail the JPG already discarded does not come back. Only worth it when you need transparency or a lossless master.
• To WebP: smallest of the three in most cases, and it keeps transparency, but confirm that wherever the file is going accepts it.
• No AVIF: it compresses better again, but encoding support in browsers is narrower than for WebP, so it is not offered here.

EXIF metadata is dropped. Re-encoding produces a clean file with no capture date, camera model or GPS coordinates. Useful before posting a photo publicly, but the wrong tool when the metadata is the point.

Animations keep only the first frame. An animated GIF or animated WebP drawn onto a canvas yields a single frame, so the output is a still image. Pixel dimensions are never changed either: this page does not resize or crop. To shrink the dimensions as well, use the image compressor.

Lossy to lossy compounds. JPG to WebP and back to JPG re-compresses twice, and the detail lost on the first pass is gone. When you are experimenting, always go back to the original file rather than converting a converted one.

Everything stays on your device. The browser decodes the image, draws it on a canvas and encodes it again, which is the local equivalent of Save As. No server here receives images, so scans of documents and contracts are no more exposed than in your own file manager.