Converter
An 800KB PNG drops to around 120KB as a JPEG at quality 85. Side by side in a browser, most people cannot tell them apart. Multiply that across a full page of images and the load time difference is not subtle.
This guide covers everything about the converter above: which quality setting matters, how transparency is handled, what the output will look like, when JPEG is the right choice versus WebP, and what to do when something goes wrong.
Why PNG Is Usually the Wrong Format for Web Photos
PNG and JPEG solve different problems. They are not interchangeable.
PNG is lossless. Every pixel is stored exactly. That makes it the right format for logos, icons, screenshots, and anything with hard edges or text on a transparent background. The file does not guess. It knows exactly what color every pixel should be.
JPEG is lossy. It discards image data your eye is unlikely to notice, specifically fine detail in areas of similar color. The result looks the same to most people but the file is a fraction of the size.
The problem: PNG ends up used for everything by default, including photographs and banner images where exact pixel-level accuracy does not matter. A high-resolution photo saved as PNG typically runs 2 to 5MB. The same photo as a JPEG at quality 85: 200 to 600KB. At quality 60: 80 to 200KB.
For a page with ten images, converting from PNG to JPEG at quality 85 often saves several megabytes per load. On a slow mobile connection that is measurable. Pages that take eight seconds to load lose visitors. Pages that take two seconds do not.
JPEG vs WebP: Which Should You Use in 2025?
JPEG is not the only alternative to PNG. WebP is worth knowing about before you convert.
WebP is a modern image format developed by Google. Lossy WebP files run 25–34% smaller than JPEG at equivalent visual quality. Lossless WebP files run about 26% smaller than PNG. WebP also supports transparency, which JPEG does not. Browser support sits at around 96–99% globally as of 2025, making it a practical choice for most websites.
So when should you use JPEG instead of WebP?
- Maximum compatibility: Email clients, older CMS platforms, print workflows, and some third-party systems handle JPEG better than WebP.
- Legacy systems: If your pipeline or platform does not support WebP, JPEG is the right target.
- Simplicity: JPEG works everywhere without fallbacks. WebP on older systems may require a PNG or JPEG fallback in your HTML.
If your images go directly onto a modern website with no compatibility constraints, WebP often gives you smaller files at the same visual quality. This converter produces JPEG. For web use, consider also running your images through a WebP converter after converting from PNG.
How This Converter Works
You upload a PNG, pick a quality level, and the server processes it using PHP’s GD image library. The converted JPEG saves to the site’s media library and you get a download link.
Nothing goes to an external service. No third-party API. No cloud pipeline. The conversion happens on this server.
One thing it handles automatically: PNG supports transparent backgrounds and JPEG does not. Rather than producing a broken image, the converter fills transparent areas with a white background before encoding. That is the standard behavior in Photoshop and every other image editor. More on transparency below.
Understanding Quality Settings
Quality runs from 1 to 100. It controls how hard the JPEG encoder compresses the image. Lower numbers mean smaller files with more visible degradation. Higher numbers mean larger files that look closer to the source.
Almost every web image belongs between 60 and 95. Outside that range you are either degrading the image or gaining nothing.
Quality 40 to 60: Artifacts are visible, especially around sharp edges and text. Files are very small. Fine for background images nobody examines closely, or thumbnails under 150 pixels wide. Anything above that and you will probably notice the compression.
Quality 70 to 80: Minor artifacts you usually have to zoom in to find. Works for secondary content images, sidebars, and blog thumbnails where people are reading, not scrutinizing the photo.
Quality 82 to 88: Where most images on most professional websites land. Google and Facebook compress user uploads to this range. Artifacts are not visible at normal screen sizes. This is quality 85 by default in the converter, and for most purposes you do not need to change it.
Quality 90 to 95: Near-lossless. Artifacts are essentially invisible even zoomed in on a high-density display. Use this for product photography or anything where image quality is part of what you are selling.
Quality 96 to 100: No visible improvement over 90 to 95 in a browser, but the file gets meaningfully larger. Only worth it if you are storing a copy you plan to re-edit or re-export later.
The Four Presets
Small — Quality 60
For images that are decoration rather than content: background images, category icons, author avatars, newsletter thumbnails. The file is very small but compression artifacts will show in fine detail or sharp color transitions. Check the preview carefully before using this on anything with text or thin lines.
Balanced — Quality 85
Right for most images on most sites. Blog post photos, page banners, team headshots. Output looks clean in a browser and the file size reduction versus PNG is significant. If you are converting a batch without evaluating each one, leave it here.
Sharp — Quality 92
For images people actually look at. Product photos on a store, portfolio work, real estate photos, high-resolution hero images. At 92, artifacts are essentially invisible and the output holds up when someone zooms in or opens it on a Retina screen.
Max — Quality 100
Use Max only for working copies you plan to edit again, not for images going live on a page. It offers no visible advantage over Sharp for display, and the files are noticeably larger. Most people who reach for Max do not actually need it.
How to Convert Your PNG to JPEG
Step 1: Check the file first
The converter validates the file type on the server, not just the extension. Renaming a JPEG to .png does not work. PNG files come from Figma, Photoshop, screenshot tools, or any editor exporting lossless. Photos from a phone are almost always JPEG already.
Also: the converter does not resize. A 4000-pixel-wide PNG becomes a 4000-pixel-wide JPEG. Resize in your image editor before uploading if you need a smaller output.
Step 2: Upload
Drag the file onto the drop zone or click to open the file picker. The file name and size appear as confirmation once it loads. Any file type that is not PNG gets rejected before anything uploads.
Step 3: Pick your quality
Move the slider or click a preset. If you are unsure, leave it at 85. You can always go back, adjust, and convert again.
Step 4: Convert
The file uploads, the server validates it, fills any transparent areas with white, applies compression at your chosen quality, and returns a preview. Most files take two to eight seconds depending on size and your connection.
Step 5: Check the preview before downloading
Zoom in on fine detail, edges, and gradients. If something looks blocky or soft in a way that bothers you, go back and increase the quality. At 85 and above, most photographic images come back looking clean.
Step 6: Download
Click Download to save the JPEG. The file also goes into the WordPress media library automatically, so you can insert it into any post or page without re-uploading.
Transparency
Transparent backgrounds are one of the main reasons people reach for PNG. Logos, cutouts, and overlays that need to sit on different colored backgrounds all rely on transparency.
JPEG has no transparency channel. Every pixel needs a solid color. When the converter hits a transparent area, it fills it with white.
That is fine if the image appears on a white or light background. A product photo on a white cutout converts without any visible change.
It is a problem if the image sits on a dark or colored background. The white fill becomes a visible white box around your subject. Do not convert to JPEG in that situation. Keep the PNG or use WebP, which supports transparency in both lossy and lossless modes.
Semi-transparent areas like soft shadows or feathered edges also get filled with white. Around blurred edges the result looks slightly different from the original.
Short version: if transparency is load-bearing in how the image works, keep the PNG. If the image only ever appears on a white background, converting is fine.
File Size Expectations
How much smaller the output will be depends on the image content, the quality setting, and the original PNG’s bit depth.
Photographs and images with lots of color variation compress very well to JPEG. A 2MB photographic PNG often becomes 200KB at quality 85 without visible quality loss.
Images with flat color, geometric shapes, or text do not compress as efficiently. JPEG struggles with sharp edges and produces visible artifacts. For these images, PNG is often the better format anyway since they tend to be small as PNG already.
Rough output sizes for photographic images by quality setting:
- Quality 60: roughly 5 to 15 percent the size of the source PNG
- Quality 85: roughly 10 to 25 percent the size of the source PNG
- Quality 92: roughly 20 to 40 percent the size of the source PNG
- Quality 100: roughly 40 to 70 percent the size of the source PNG
Every image compresses differently. These numbers are a starting point, not a guarantee.
Image Format, SEO, and Page Speed
Image format affects your search rankings. Page speed is a direct Google ranking factor, and images are responsible for the Largest Contentful Paint (LCP) on 85% of desktop pages and 76% of mobile pages, according to the 2025 Web Almanac. LCP is one of Google’s Core Web Vitals.
Converting large PNGs to JPEG at quality 85 cuts file size by 75–90% for photographic images. That alone moves the needle on load time for most image-heavy pages.
If you want to go further, Google’s PageSpeed Insights flags PNG and JPEG and recommends “next-gen formats” like WebP and AVIF. WebP files run 25–34% smaller than JPEG at the same visual quality. AVIF goes further still, with 50%+ savings over JPEG, though browser support sits at 94.7% as of 2025 compared to WebP’s near-universal coverage.
A practical workflow for WordPress sites:
- Convert photographic PNGs to JPEG using this converter.
- Upload to your media library.
- Use a plugin like ShortPixel or Imagify to automatically serve WebP versions to browsers that support it, with JPEG as the fallback.
This gives you broad compatibility and the smallest possible files for modern browsers, without any manual work per image after setup.
Frequently Asked Questions
Can I convert multiple PNG files at once?
One at a time. After downloading, upload the next PNG and convert again. The page does not need a refresh between conversions. For large batches, a tool like ImageMagick or a desktop editor will be faster.
Will the dimensions change?
No. Width, height, and DPI carry over exactly. Only the format and compression change.
The output looks blurry or has blocky patches. What do I do?
The quality setting was too low for that particular image. Increase it to 90 or above and convert again. Images with fine detail, text, or hard edges are more sensitive to JPEG compression than photographs with smooth gradients.
Should I convert to JPEG or WebP for my website?
For most websites in 2025, WebP is the better target. It is 25–34% smaller than JPEG at equal visual quality and supports transparency. Use JPEG when you need maximum compatibility with older systems, email clients, or platforms that do not support WebP.
I got an error saying the file is not a valid PNG.
The converter checks the actual file type on the server, not just the filename extension. If this error comes up, the file is probably a JPEG or WebP with a .png extension. Open it in an image editor to confirm the real format.
Is there a file size limit?
The limit is set by the server’s PHP upload configuration. If a large file fails, reduce the image dimensions in your editor first, then convert.
The preview looked fine but the download link did not work.
The file is in the media library. Refresh the page, convert again, and download immediately after it finishes.
Does it work on mobile?
Yes. The drop zone, slider, presets, and download button all work in mobile browsers. Use your phone’s file picker to select from Photos or Files.
Are converted files private?
Files save to the site’s uploads folder. On a public website, they are technically accessible via direct URL like any other media item. If you are converting something sensitive, download it and delete it from the media library in the WordPress dashboard.
Tips
Check the preview before you download. A few seconds looking at fine detail can save you from publishing a blurry image.
Resize before converting. If the PNG is larger than its intended display size, resize in your editor first. Converting a 4000-pixel-wide image and then scaling it in WordPress gives you a larger file than you need.
Logos and icons should stay as PNG. Flat colors and hard edges do not compress well to JPEG. They look worse and the PNG is usually small already. There is no real benefit to converting them.
Images with text need a higher quality setting. JPEG handles text badly below quality 90. If your PNG has readable text in it, check the output at 92 or above before publishing.
Do not default to Max. Quality 92 and quality 100 look identical in a browser. 92 produces a smaller file. Use Max only when you have a specific reason.
Consider WebP for web images. After converting PNG to JPEG, run the file through a WebP converter for your website. WebP is 25–34% smaller than JPEG at the same quality, and nearly every browser supports it in 2025. Many WordPress image optimization plugins handle this automatically.
