"Format not supported" is one of the most annoying messages in daily work. A website that wants PNG and refuses WebP, a hiring platform that wants JPEG while your picture is PNG, or the opposite: images you downloaded from the internet in WebP that your software cannot open.
The answer is not hunting for a site that uploads your images to convert them on its servers. The answer is a tool that changes the format on your device in seconds, in one batch, with full control over quality.
In this guide we explain the difference between the three core formats, when to pick each one, and how to convert your images without losing anything that cannot be recovered.
The difference between PNG, JPEG and WebP
The three formats serve different purposes, and understanding them saves you a lot of trial and error:
- PNG: keeps the image complete with no loss and supports transparency. Ideal for logos, screenshots, designs and photographed text, but the largest of the three.
- JPEG: compression with controlled loss. Ideal for photographs because it shrinks the size considerably, but it does not support transparency at all.
- WebP: combines both almost — small size and transparency support — but its compatibility is lower with older software and some systems.
A useful general rule: photographs to JPEG, logos and screenshots to PNG, and web page images to WebP.
A comparison table of the three formats
| Criterion | PNG | JPEG | WebP |
|---|---|---|---|
| Image quality | Complete with no loss | Compression with controlled loss | Compression with controlled loss |
| Transparency support | Yes | No | Yes |
| Size for the same image | Largest | Usually smallest | Very small |
| Best for | Logos, screenshots, designs | Photographs | Web pages |
| Compatibility with software | Excellent everywhere | Excellent everywhere | Lower with older software |
| Camera and date metadata | No | Usually kept | Usually kept |
| Repeated editing without degradation | Yes | No — every save loses more | No, if lossy compression is used |
An important point from the table: converting a compressed format to PNG does not bring back lost detail. If you convert a JPEG to PNG it will not become sharper; it will only become bigger. Lost quality is not recovered.
How to convert image formats — step by step
- Open the Image Format Converter on TaskDo. No sign-up, no software to install.
- Choose one image or several, or drag and drop them into the drop area.
- Select the target format: PNG, JPEG or WebP.
- Adjust the quality if you chose JPEG or WebP. The default value gives a good balance between size and sharpness for most uses.
- Press "Convert". The processing happens inside your browser and the images are never uploaded to any server.
- Download the new images individually or as a single ZIP file.
Convert to JPEG to reduce size before sending, to PNG to edit an image without extra loss, and to WebP to speed up web pages. And do not expect a conversion to recover detail the image has already lost.
Quality control: what it means and how to pick it
When you choose JPEG or WebP you see a quality slider. A higher value means a sharper image and a larger file; a lower value means a smaller file with a visual difference you may notice when you zoom in.
- For on-screen use and sending: a medium to high value gives an excellent result with a clear saving in size.
- For archiving and repeated editing: prefer PNG, because every save in a compressed format costs the image an extra amount of detail.
- For high-quality printing: PNG is the safest choice, or JPEG at the highest quality available.
The best practice is to try two values and compare the result with your own eyes before converting dozens of images. A difference you cannot see on your screen will not be seen by whoever receives the picture.
The tool's limits you should know
- Dimensions do not change: the tool changes the encoding only, and the image's dimensions stay the same. To shrink the dimensions use the Resize Image tool.
- Transparency and JPEG: when converting to JPEG, transparent areas become white because the format does not support transparency at all. If transparency matters in your image, convert to PNG or WebP.
- HEIC photos from an iPhone: this depends on your browser's support for the format. If the browser cannot open them, a message will say so.
- Number of images: no limit on our side, but the practical limit is set by your device's memory.
Tips for the best result
- Choose the format from the requirements, not from habit. Read what the website or platform asks for before you convert.
- Do not convert a compressed format to PNG expecting better quality — that is not possible, and the right habit is keeping the high-quality original from the start.
- If the file will be uploaded to a portal that requires a specific format and a maximum size, convert first and then compress if it is still too large.
- For logos and designs always use PNG, even if the size is larger — transparency and sharp edges matter more than a few kilobytes.
- Keep the original version. Converting produces new files and never edits your images.
- Try the conversion on one image and inspect it zoomed in before converting the whole batch.
Frequently asked questions
Is transparency preserved when converting?
It is preserved when converting to PNG or WebP. When converting to JPEG, transparent areas turn white because the format does not support transparency.
Do the image dimensions change after conversion?
No. The dimensions stay the same and only the encoding changes. To shrink the dimensions use the Resize Image tool.
Can I convert HEIC photos from an iPhone?
That depends on your browser's support for the format. If it cannot open them, a message will say so.
Does converting to PNG improve the quality of a JPEG image?
No. Converting a compressed format to PNG does not bring back lost detail; it only increases the size. Lost quality is not recovered.
Are my images uploaded to any server?
No. The processing happens entirely inside your browser and the images are never sent to any external server.
Is the tool free and does it work on a phone?
Yes, the tool is completely free and works on any device with a modern web browser — desktop, phone or tablet.
Can I convert several images in one batch?
Yes, pick several images in the same run, choose the target format, and download them individually or as a single ZIP file.
Related tools you may need
Summary
Converting image formats between PNG, JPEG and WebP is now a matter of seconds that happens on your device. With the Image Format Converter on TaskDo you pick the required format in one click, control the quality, and convert a whole batch in the same run — and no image ever leaves your browser.
Remember the golden rule: PNG for logos and transparency, JPEG for photographs, WebP for web pages. And never expect a conversion to recover quality the image has already lost.