How to Convert PNG to WebP for Smaller Files on Websites

Yes — and for web use, WebP is almost always better than PNG. WebP lossless files are typically 25–35% smaller than equivalent PNGs, with identical visual quality. WebP lossy files are even smaller (5–10× smaller than PNG) and look the same as PNG to the human eye.

Last updated: 2026-07-19

Why convert PNG to WebP for the web

PNG is the right format for editing and design. For web display, WebP is the modern choice:

Smaller files mean faster page loads and better Lighthouse scores
Google PageSpeed Insights explicitly recommends WebP over PNG
All modern browsers support WebP (Chrome, Firefox, Safari 14+, Edge)
WebP supports transparency (lossless WebP keeps alpha exactly like PNG)

3 ways to convert PNG to WebP

1. Use Photoshop, Affinity, or the cwebp CLI tool

Photoshop (2020+) and Affinity Photo can open PNG and export as WebP. The cwebp command-line tool from Google is the gold standard for batch PNG → WebP conversion, but it's a command-line tool, not a GUI. Downsides: Photoshop is paid and 2GB+ to install; cwebp requires comfort with the terminal.

2. Use an online PNG to WebP converter

Websites like CloudConvert, Convertio, and Squoosh convert PNG uploads to WebP. They work for one-off files but every image uploads to a server. Most cap file size at 25–100 MB, and PNG files (especially screenshots) often exceed that. Your images sit on a stranger's server during the conversion.

3. Use EasyImg (desktop, local, batch)

EasyImg is a desktop app for Windows and Mac that converts PNG to WebP entirely on your computer. Drag in a folder of PNGs, pick WebP, click Convert. Lossy WebP at quality 90 (default) is about 5–10× smaller than the source PNG with no visible difference; lossless WebP is about 25–35% smaller with bit-identical output. A typical PNG converts in about 0.3 seconds; 200 images finish in a minute. Transparency is preserved (lossless or lossy with alpha). No upload, no file size cap, no internet required.

How to convert PNG to WebP with EasyImg

Drop in your PNG files

Single files, folders, or both. Screenshots, graphics, and photos all work.

Pick WebP and set quality (or lossless)

Default 90 lossy is invisible to the eye at 5–10× smaller files. Switch to lossless for pixel-perfect output (logos, master files).

Click Convert

Files land in the same folder with .webp extension. Duplicates skipped, conflicts auto-rename. Transparency is preserved.

PNG to WebP: which method is best?

	Online converter	Photoshop / cwebp CLI	EasyImg (Desktop)
Privacy	Uploaded to a third-party server	Stays on your disk	Stays on your disk
Speed per image	5–10 seconds	1–3 seconds (Photoshop) / faster via cwebp	~0.3 seconds
Batch	5–10 files at a time	cwebp CLI: yes. Photoshop: action script.	Whole folders at once
File size cap	25–100 MB (PNG often exceeds)	No limit	No limit
Ads / popups	Banner ads, signup walls	None	None
Works offline	No	Yes (after install)	Yes

PNG to WebP — common questions

Yes — both lossless and lossy WebP support full alpha channel transparency. The output preserves the exact alpha mask of the source PNG. Lossy WebP with alpha is slightly larger than lossy without, but the difference is usually small (a few percent).

Yes, for almost all web cases. Lossy WebP at quality 80–85 is visually identical to PNG for typical web graphics and 5–10× smaller. Lossless WebP is about 25–35% smaller than PNG with bit-identical output. Google PageSpeed Insights explicitly recommends WebP. The only reason to stay on PNG is if you need to support very old browsers (pre-2020).

WebP for almost every web case. JPG is slightly smaller than lossy WebP for photos, but JPG doesn't support transparency. If your PNG has transparency (logos, icons, design assets), use WebP — JPG would force a solid background. If your PNG is a photo and you don't need transparency, JPG is a fallback for very old browsers; otherwise WebP.

All modern browsers support WebP: Chrome (since 2014), Firefox (since 2019), Edge (since 2018), Safari (since version 14, 2020), and all mobile browsers. Pre-2020 browsers don't support WebP — for those, you'd need a JPG/PNG fallback.

EasyImg preserves EXIF in the WebP output. Most online converters strip EXIF to save bandwidth. Note that for web use, EXIF is rarely needed — most browsers don't display EXIF for WebP images anyway.

Yes. Drag a folder of 5,000 PNGs into EasyImg, pick WebP, click Convert. Even at 0.3 seconds per file, 5,000 files finish in about 25 minutes. The output is dramatically smaller — 5–10× for lossy WebP at quality 90. If you host those images on a website, you'll see faster page loads and less bandwidth.

Other conversions you might need

Bottom line

For web use, WebP almost always beats PNG. Lossy WebP is 5–10× smaller with no visible difference; lossless WebP is 25–35% smaller with identical pixels. Both modes support transparency. For non-web use (editing, design, master files), stay in PNG. EasyImg does the conversion locally so your images never leave your computer.

Why trust EasyImg

EasyImg is built for people who care where their photos go. Everything below is verifiable in the app itself.

100% offline — your images are processed on your own device and never uploaded to any server.
Powered by libvips, the mature open-source imaging engine also used by Squoosh and major platforms.
Free and open under the LGPL license — no lock-in, no hidden data collection.
Native apps for macOS and Windows, updated regularly.