PNG to JPG Converter
Use the CaseSwitch PNG to JPG Converter to rasterize a PNG to JPEG in your browser with the Canvas API. Transparency is flattened onto a white or black background. Files are never uploaded.
Written by the CaseSwitch editorial team. We maintain these tools in the browser so drafts, keys, and images stay on your device.
Last reviewed: 23 July 2026
Images are converted in your browser with the Canvas API. Nothing is uploaded.
Drag and drop a PNG here, or choose a file
Examples
Screenshot with transparency → white matte
Input
ui-shot.png (alpha around chrome)
Output
ui-shot.jpg · transparent pixels composited on #ffffff
Screenshot with transparency → black matte
Input
ui-shot.png · background: black
Output
ui-shot.jpg · alpha flattened onto #000000
Photo PNG → smaller JPEG
Input
vacation.png (~8 MB lossless photo)
Output
vacation.jpg · quality ~0.85–0.92, typically much smaller
Quality tradeoff note
Input
diagram.png · quality 0.5 vs 0.92
Output
Lower quality → smaller file, more blockiness around edges/text
Wrong tool reminder
Input
logo-transparent.png needing alpha on the web
Output
Prefer PNG or WebP — JPG cannot keep transparency
How to use
- Choose or drop a PNG (max size enforced by the tool).
- Set JPEG quality and pick white or black for transparent areas.
- Convert and download the `.jpg` — keep the original PNG if you still need alpha.
What this tool is for
Turn PNG screenshots and graphics into smaller JPEG files for email caps, CMS uploads, and platforms that prefer JPG. JPEG has no alpha channel, so transparent pixels are composited onto the background you choose before encode. Quality defaults to 0.92 (range 0.1–1).
How it works
Your PNG is validated (type and size), drawn onto a canvas, and exported with `canvas.toBlob('image/jpeg', quality)` after an optional background fill. Object URLs stay on-device and are revoked after use when the UI can. APNG animation is not preserved as animation — you get a still frame path through Canvas.
When to use it
Photos that were saved as PNG for no good reason, email attachments with size limits, and web photos that do not need transparency.
When not to use it
Logos and UI icons that need crisp edges and alpha — keep PNG or convert with PNG to WebP instead. Screenshots heavy with text often show JPEG ringing. Do not expect to recover lossless quality by converting back to PNG later.
How it compares to related tools
PNG to WebP can keep transparency and often shrinks graphics. JPG to PNG goes the other direction and cannot invent real transparency. SVG to PNG is for vectors. WebP to JPG is the parallel flatten path from WebP.
Common mistakes
Flattening a logo onto white then placing it on a dark site, crushing quality to 0.1 and blaming JPEG in general, and deleting the PNG master after a lossy pass.
Transparency and backgrounds
JPEG has no alpha. The converter fills the canvas with white or black before drawing the PNG so formerly transparent pixels become opaque. Choose the matte that matches where the JPG will sit. Soft shadows on transparent PNGs will bake into that matte color.
Local Canvas processing
Conversion uses the browser Canvas API on your device. CaseSwitch does not upload the image. EXIF from a PNG photo path is typically not preserved through canvas re-encode. Max upload size is enforced client-side before draw.
Frequently asked questions
What happens to transparent pixels?+
They are composited onto the background color (white or black). There is no JPEG alpha.
Is the image uploaded?+
No. Canvas processing stays in the browser. Object URLs are revoked after download when possible.
What quality should I use?+
Start near the default 0.92. Lower toward 0.7–0.85 for email size caps; preview text-heavy screenshots carefully.
Will animation survive?+
No. Canvas export is a still image. Use a dedicated APNG/GIF workflow if you need motion.
Can I convert back to PNG losslessly?+
You can wrap pixels as PNG later, but JPEG artifacts remain. Keep the original PNG master.
Why is my JPG larger than the PNG?+
Rare for photos; more common for simple graphics where PNG compresses flat colors well. Compare sizes before replacing assets.
Are images uploaded to a server?+
No. Image tools use the Canvas API in your browser. Files stay on your device and object URLs are revoked after use.
Related tools
JPG to PNG Converter
A CMS that rejects JPEG, a print tool that wants PNG, and pipelines that expect a PNG extension even when content started as a photo.
WebP to JPG Converter
Printers and CMS boxes that want JPEG, Outlook-era workflows, and sharing a photo with someone whose apps lack WebP.
PNG to WebP Converter
Web performance for graphics, replacing heavy PNGs on marketing pages, and stickers that need a transparent background.
JPG to WebP Converter
Web performance passes, replacing heavy JPG heroes, and building `<picture>` experiments when you still keep a JPEG fallback elsewhere.
WebP to PNG Converter
Opening a WebP in an older editor, handing files to a print vendor that wants PNG, and keeping transparency for further design work.