Browser tool

PNG to WEBP Converter

Convert PNG to WEBP online without uploads—PolyImg uses WebAssembly, WebCodecs, and Canvas to shrink assets right in your browser, perfect for “PNG to WEBP converter” searches, Shopify performance tuning, and newsletter hero images.

Capabilities

Smaller WEBP files in seconds

Instant PNG to WEBP

Drop multi-megabyte PNGs into PolyImg and the browser converts them to lightweight WEBP files via WebAssembly and WebCodecs.

Control size & fidelity

Choose lossy/lossless, cap file sizes, resize long edges, or flatten backgrounds—all with live before/after previews.

Browser-only pipeline

No uploads, no queues—everything runs locally using Canvas/OffscreenCanvas so brand assets never leave your device.

WebAssembly codecs mirror production CDNs, ensuring the WEBP previews you see locally match what users download.
Workflow

Three steps to PNG → WEBP

  1. 1Upload or drag PNG files into the workspace—previews render instantly with WebGL acceleration.
  2. 2Pick presets (lossy, lossless, target size) or fine-tune quality sliders while watching live savings.
  3. 3Export WEBP assets in one click or copy them straight to your CMS, CDN, or design system.
  • Apply multiple presets (hero, thumbnail, email) and export them together to streamline multi-channel delivery.
  • Save conversion presets in IndexedDB so teammates keep compression rules consistent across campaigns.
Quality & privacy

Keep fidelity high and assets private

PolyImg optimizes gradients, typography, and transparency so converted WEBP files stay sharp on retina displays.

Because the converter runs entirely on-device, unreleased launches, design comps, or sensitive documents never touch a server.

FAQs

Common questions about PolyImg’s PNG to WEBP converter. Need automation or API support? Reach out.