png · webp · alpha · local

Compress PNG to WebP with alpha

Shrink PNGs into smaller WebP files while preserving transparency. Adjust quality and download — everything runs locally.

PNG to WebP
Source
—
no file
Output
—
—
Quality
90%
webp
Saved
—
ratio
Quality:90%
input · image

image/png · runs locally · nothing uploaded

output · preview
Preview appears here
Quick Start

How it works

Pick an image, tune the options, then download the result. Everything runs in your browser.

  1. 01

    Pick a PNG

    Drop or select a PNG file. Alpha is preserved.

    Files stay in memory as an HTMLImageElement — the original bytes are never uploaded, and EXIF metadata is preserved until you explicitly transform it.

    uploadcanvaslocaldecode
    input · bytespng · loaded
    image.png
    loaded · decodedcanvas · ready
  2. 02

    Tune quality

    Adjust the slider — 80–90% is usually visually identical to PNG.

    Encoder quality is exposed where the format supports it — JPEG and WebP get a 0–1 quality slider; PNG is lossless. Options re-render the canvas immediately.

    qualityoptionslive previewencoder
    quality · tunable90% · live
    encode(q=0.9)
    options applied · liveencoder · live
  3. 03

    Inspect savings

    WebP cuts size 25–50% from PNG at high quality for typical UI images.

    Pixel work runs on the Canvas 2D context — drawImage resamples with the browser’s bilinear filter and getImageData/putImageData back per-pixel passes.

    sizerenderCanvas 2Dpreviewpx-perfect
    savings · resampled0% · px-perfect
    png > webp
    preview · livepx-perfect
  4. 04

    Download WebP

    Save the WebP. All modern browsers support it natively.

    Downloads ship via a hidden anchor with an object URL — no server round-trip, and the file on disk is untouched. The output filename inherits a sensible suffix.

    exportdownloadblobclient-sideobject URL
    ok · blobready · saved
    image.webp
    shipped · ready to shipsuccess
Pro tips

Browser-only image work that scales

Convert with quality control

JPEG/WebP let you pick a 0–1 quality. Default 0.92 is a good compromise of size and visible quality.

PNG isn’t free

Use PNG only for transparency or sharp edges. For photos, WebP is smaller at the same perceived quality.

Strip EXIF for privacy

Photo EXIF often contains GPS, camera model, and timestamps. Strip before sharing public uploads.

Watch the colour profile

Convert to sRGB before web export. Wide-gamut images render oversaturated in non-managed browsers.

AVIF when it’s available

AVIF beats WebP on size at the same quality. Detect support via <picture> with fallbacks.

Lazy-load below the fold

Add loading="lazy" on <img>. The browser handles scheduling — no IntersectionObserver needed.

Use Cases

When to use this tool

Common workflows it speeds up.

Web performance

Smaller assets, faster page loads. Decoded into a Canvas 2D context — original bytes never leave the tab, so you can process customer-uploaded photos, internal screenshots, or sensitive diagrams without privacy concerns.

px-perfect

Hero images

PNGs with subtle gradients halve in size as WebP. Encoders expose quality 0–1 where the format supports it (JPEG, WebP); PNG and AVIF stay perceptually lossless. Pick 0.85 for web, 0.95 for archival, 0.7 for thumbnails.

quality-tunable

Sticker packs

Transparent stickers keep their alpha. Pair with the EXIF Stripper before sharing user-uploaded photos publicly. Camera serial numbers, GPS coordinates, and timestamps often hide in image metadata and leak more than the picture itself.

format-aware

Game/app assets

Lighter texture downloads. Output preserves colour profile (sRGB) so it renders consistently across browsers, monitors, and print pipelines. Wide-gamut workflows can opt into Display P3 for modern Apple devices.

EXIF-safe

OG images

Modern preview thumbnails in WebP. Re-runs only on option changes, never on window resize, so the canvas stays responsive on large images. drawImage uses the browser's bilinear filter for fast resampling.

client-side

CDN savings

Bandwidth bill down without quality loss. Downloads as .png, .jpg, .webp, or .avif with the correct MIME so editors apply native handling on save. The filename inherits a sensible suffix derived from the input.

compression-ready
FAQ

Frequently asked questions

Yes — WebP carries an alpha channel just like PNG.
Often 25–50% smaller at quality 80–90, sometimes much more for photographic content.
WebP is lossy at the chosen quality. Pick 90+ for near-PNG fidelity.
Yes — Chrome, Firefox, Safari 14+, and Edge all decode WebP natively.
No. Everything runs locally in your browser.
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