Image Converter (JPG, PNG, WebP)

What is an image converter and what does this tool do?

An image converter keeps a picture's content and changes its file format. For example, turning a JPG into a PNG, a PNG into WebP or a WebP into JPG are typical conversions. When the format changes, the file size, the transparency support and the list of programs that can open the file change too. Picking the right format is therefore much faster than preparing the picture again.

This tool does the following:

• The target format can be JPG, PNG or WebP.
• A single file converts as readily as a batch of up to 100 files.
• Every file gets its size before and after, plus the percentage change.
• The EXIF orientation applies, so a sideways phone photo comes out upright.

First, everything runs in your browser. Your file never reaches our server, and we store nothing. Our team also meets this task most often while preparing website images. For example, in web design projects, a single image in the wrong format can slow down a whole page.

Which format should you choose with an image converter, and when?

The choice comes down to three questions. Does the picture need transparency? Is it a photo, or does it contain sharp lines and text? Where will you upload it? So these three answers almost decide the format on their own.

• JPG: This is the most common choice for photos. It compresses with loss and carries no transparency, but every system can open it. Therefore it suits form uploads and email attachments.
• PNG: It is lossless and keeps transparency. For example, screenshots, logos and graphics with text keep crisp edges. For photos, however, the file often grows.
• WebP: It works both lossy and lossless and supports transparency. It is also the best candidate for website speed. Still, not every older program opens WebP.

The numbers back this up. According to Google's WebP documentation, lossless WebP is 26% smaller than PNG. Lossy WebP is 25-34% smaller than comparable JPEG at an equivalent SSIM quality index. These are Google's own measurements, and your image may behave differently. Therefore check the size before and after in the preview.

If you prepare images for a website, our guide on how to optimize images for website speed and SEO also covers size and loading order.

How does the tool recognise a format without trusting the extension?

The tool does not trust the file extension. It reads the first bytes of the file and finds the format from those markers. Then it shows the result on each row as Detected format, with a label such as "WEBP → PNG".

So this solves an everyday problem. Many websites serve images as WebP, but the extension may still say .jpg after you save one. As a result, some programs cannot open such a file. Because the tool recognises the real format, it still converts the file correctly.

Also, the tool can open these inputs:

• JPG, PNG, WebP, GIF, BMP and AVIF.
• Other formats that your browser can open.
• HEIC: only a browser that supports it can open it, and Safari is one example. If your browser cannot, the tool says so openly.

For animated GIF and WebP files, only the first frame converts, and the tool warns you about it. However, if you need the animation, a single-frame output will not help. Instead, keep the original file.

How do batch conversion and the ZIP download work?

First, you can add up to 100 files to the panel at once. Drag and drop them, pick several with the Choose images button, or paste a copied picture with Ctrl/Cmd+V. Then the tool opens a separate row for every file.

Each row shows this information:

• A small preview and the file name.
• The direction of the conversion, for example "WEBP → PNG".
• The size before and after, plus the percentage change.
• A Download button for that single file.

The list also includes a summary: the number of files, the total size before and after, and the overall change. Finally, to take everything in one go, press Download all as ZIP.

Also, when you change a setting, the list converts again on its own. For example, if you switch the target from PNG to WebP or move the quality slider, you do not need to add the files again. So you can try a few options quickly and keep the best result. For jobs with dozens of pictures, such as a product catalogue, this also saves a lot of time.

What does the quality setting mean, and which value should you pick?

The quality slider appears only for lossy output, which means JPG and WebP targets. Lossy compression shrinks a file by dropping detail that the eye barely notices. The lower you pull the slider, the smaller the file gets, but the risk of blocky areas and blur grows. The default is 92%, so the tool starts with a setting that keeps quality high.

PNG is lossless, so the tool hides the slider for PNG. Instead, a PNG stores every pixel as it is, which leaves no loss to adjust.

A practical method works like this:

1. Start with the default 92% and look at the resulting size.
2. Then, if the file is still too big, lower the quality in small steps.
3. Also watch text edges, flat areas such as sky, and fine detail in faces in the preview.
4. Finally, if you see damage, go one step back.

Converting a lossy file to another lossy format again and again removes a little more detail every time. For that reason, keep your original file and make each new version from it.

What happens to a transparent background when you convert to JPG?

JPG carries no transparency. When you convert a PNG or WebP with transparent areas to JPG, those areas need a colour. For this reason the tool offers the Colour for transparent areas option: White (the default), Black or Custom colour.

So the colour you choose changes the result directly. For example, if you pick white for a light logo, the logo disappears. A dark logo reads well on White, while a light logo works better on Black or on a contrasting custom colour.

Instead, if you want to keep transparency, set the target to PNG or WebP. MDN states that PNG supports full alpha transparency and that JPEG does not support an alpha channel. Google also notes that WebP supports transparency in both lossless and lossy mode.

One misunderstanding is worth correcting: converting a JPG to PNG does not make the background transparent. Because the conversion only changes the format, it cannot create transparency that the source file lacks. Removing a background is a separate editing job.

Are your files uploaded, and what happens to EXIF and location data?

No, they are not uploaded. Once the page has loaded, the whole process runs in the browser on your device. Your file never reaches our server and nobody stores it, so we cannot see it either. For sensitive files such as an ID, a contract or a client photo, that is also a real advantage.

Let us be honest about metadata. The tool applies the EXIF orientation, so a sideways phone photo comes out upright. However, it builds the new file by redrawing the pixels, so metadata such as EXIF and GPS does not carry over to the output. That has two consequences:

• A privacy advantage: When you share the photo, location and device details do not leave by accident.
• A drawback: If you need to keep copyright, capture date or camera settings, this tool does not fit. Then archive the original file separately.

In short, the tool suits copies you plan to share. In practice, you should keep a separate backup for archive-grade originals.

Is converting a format the same as resizing an image?

No. An image converter changes only the file format, and the pixel size stays the same. So it does not resize width or height. If you want to bring a picture from 4000 pixels wide down to 1200 pixels, the Image resizer does that job.

• Format conversion: It picks JPG, PNG or WebP, and the pixels stay the same.
• Resizing: It changes width and height, and it can also push a file toward a target KB value.

In practice, combining both jobs is a common scenario. First reduce the picture to the width you will actually use, then convert it to a suitable format. As a result, this order usually gives the smallest file on the web. We cover the effect of images on page speed in our posts on Core Web Vitals and on how site speed affects SEO.

However, if your site is slow, images may not be the only cause. In that case, we can look at the technical picture together as part of SEO consulting.