How it works

What this tool does

Convert JPG, PNG, or WebP images into optimized WebP • with optional resizing, custom naming, and a powerful side-by-side compare view.

Privacy

• Everything runs in your browser. No uploads, no servers • images never leave your device.
• Conversions use the browser’s built-in Canvas/WebCodecs where available.

Supported formats

• Input: JPG/JPEG, PNG, WebP
• Output: WebP (quality 10–99)

Resizing

• None: keep original dimensions.
• Max width or Max height: constrain the image; aspect ratio is preserved.

Q values

• Throughout this tool you’ll see references like Q70 or Q85. “Q” stands for the quality setting (1–100) used when encoding WebP. Lower values create smaller files but may introduce blur or banding, while higher values preserve more detail at the cost of larger files.
• As a rule of thumb: Q70 often reduces size by ~60% with little visible loss. Q85 gives near-original quality with moderate savings.

Naming

• Add an optional postfix (e.g. -retina), and optionally append the quality number.
• Examples: photo.webp, photo-test.webp, photo-test-80.webp.

Compare mode

• Select any versions (Original, Q70, Q80, etc.) and compare side-by-side.
• Fit view: zoom up to the native pixel size of the smallest image (no fake sharpness).
• True size (Fit off): locked at 100% to avoid misleading upscales.
• Move the cursor over one image to pan all images to the same region for easy inspection.

Batch downloads

• Download single files, or ZIP everything at a given quality.
• Smart button text: “Download” (one file), “Download All” (one quality across many files), or “Download All – Q70/Q80…” (multiple qualities).

Tips

• For the web, try between Q70 and Q85 as a starting point. Use compare to verify detail and banding.
• Large images? Consider constraining to 1920 or 2560 width for faster page loads.

Limitations

• EXIF metadata isn’t preserved.
• Animated formats (GIF/WebP) aren’t supported yet.