Google Told Me My Images Were Costing Me Rankings
I ran a Lighthouse audit on my portfolio site for the first time and the results were uncomfortable. The "Serve images in next-gen formats" warning was flagged for every single image on the page — all of them PNGs exported from Figma. My total image payload was over 4MB. I converted them all to WebP in one batch, re-uploaded, and ran the audit again. Image payload dropped to 840KB. My PageSpeed score went from 48 to 81. Nothing else changed. Just the format.
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Why Figma, Canva, and every design tool defaults to PNG — and why that's wrong for web delivery
Design tools default to PNG because it's lossless — they don't want to make assumptions about acceptable quality loss. That's reasonable for a design tool. It's unreasonable for a web server. Every PNG I export from a design tool for a website gets converted to WebP before upload. That's now automatic in my workflow.
The numbers from my actual projects
I've been tracking PNG vs WebP sizes across projects for about a year. Here's what I've seen consistently:
- Photography and hero images: WebP is reliably 50–70% smaller than PNG at quality I can't distinguish on screen. This is where the conversion pays off the most.
- Screenshots and UI images: WebP is 30–50% smaller. Still meaningful, but the gains are less dramatic because PNG's lossless compression is already fairly efficient on UI content.
- Flat-color logos and icons: Sometimes WebP is only 10–20% smaller, and occasionally PNG wins. For very simple graphics, I test both and use whichever is smaller.
- Transparent images: WebP handles alpha channels and tends to be smaller than a transparent PNG at comparable quality. I now convert all my transparent UI assets to WebP.
When I keep PNG and don't convert
WebP is my default for web delivery, but not for everything:
- Design masters and editing files: My working files stay as PNG. WebP is for delivery, not for files I'll edit again.
- Email campaigns: Many email clients don't support WebP. For anything going into an email, I use PNG or JPG.
- Sharing with people who might open on older software: If I'm handing off to a client who uses old Office or Windows 7, PNG is safer than WebP.
Files processed and deleted — no retention
Your PNGs are received over HTTPS, processed in temporary storage, and deleted as soon as the conversion finishes. No account needed, no file retention.
Frequently Asked Questions
Does converting PNG to WebP actually help my page speed score?
Yes. Google PageSpeed Insights flags PNG images under "Serve images in next-gen formats" and counts WebP as the answer. Smaller images also improve Largest Contentful Paint, which is a ranked Core Web Vital.
I have transparent PNGs. Will WebP keep the transparency?
Yes. WebP supports alpha transparency. Your transparent logos and UI overlays remain transparent after conversion.
What if some visitors are on browsers that don't support WebP?
WebP is supported by Chrome, Firefox, Safari (14+), and Edge — covering the vast majority of current users. For safety, serve WebP with a PNG fallback using the HTML <picture> element.
Will I notice quality differences from the original PNG?
For photos, typically not at normal viewing sizes. For graphics with very fine 1-pixel detail, slight softening may appear. Use lossless WebP if you need pixel-perfect output.
Can I batch convert a folder of PNGs?
Yes. Upload up to 30 files and download the results as a ZIP.
Other tools in this workflow
Resize image · Remove image background · Convert HEIC to JPG
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