Convert to WebP — JPG to WebP & PNG to WebP Online

WebP is a modern format that often beats JPG and PNG on file size while keeping good quality. Convert locally with JSM-Image.com — no account required.

How to convert to WebP in four steps

1. Add your images. Drop JPG, PNG, HEIC, AVIF, or GIF files onto the tool, or pick them with the file picker. Everything is read locally by your browser — no uploads, no waiting, no account.
2. Choose WebP as the output format. Under the format options, select WebP. The tool converts each file while keeping its pixel dimensions, unless you also choose to resize.
3. Set the quality. For photos, 80–85 gives files roughly 25–35% smaller than an equivalent JPG with no visible difference. For graphics with flat colors or text, try 85–90 or the lossless option. The live size estimate shows the result before you commit.
4. Download. Save files individually or, for many images, convert the whole batch at once and download a single ZIP.

What WebP is and why it is smaller

WebP is an image format developed by Google, built on video-compression techniques. In plain terms, it describes what a picture looks like with fewer bytes: smarter prediction of neighboring pixels, more efficient encoding of smooth gradients, and a modern entropy coder. The result is typically 25–35% smaller than JPG at the same visual quality.

WebP also has a lossless mode like PNG — often 20–25% smaller than PNG for the same pixels — plus support for transparency and even animation. That makes it a genuine all-rounder: one format that can replace JPG for photos, PNG for graphics, and GIF for simple animations.

Quality setting guidance

The quality slider is the main lever. Because WebP's encoder is efficient, you can usually go a few points lower than you would with JPG:

• Photos: 80–85. The sweet spot for web images — visibly identical to the original at normal viewing sizes, roughly a third smaller than JPG.
• Graphics, logos, screenshots: 85–95, or lossless. Sharp edges and text show artifacts first, so stay high. For pixel-perfect UI assets, lossless WebP beats PNG on size.
• Thumbnails and previews: 70–75. Small display sizes hide compression well, so you can push further for avatars, previews, and lazy-load placeholders.

Judge quality at the size the image will actually be shown — an 85-quality WebP viewed at 800 px looks flawless even if pixel-peeping reveals softening.

WebP vs JPG vs PNG vs AVIF: which should you choose?

• JPG — keep it when maximum compatibility matters: print workflows, old desktop software, or email clients that may not preview WebP. For universal photo sharing, JPG is still the safest file to send.
• WebP — the best default for website images today. Smaller than JPG, supports transparency like PNG, and opens in all modern browsers. If you are optimizing a site, convert here first.
• PNG — keep for lossless needs where you want zero risk and zero thought: screenshots for documentation, images that will be edited again later.
• AVIF — even smaller than WebP for photographs, but slower to encode and slightly less widely supported in older tools. Worth it for hero images and portfolios; overkill for everyday sharing.

Transparency: converting PNG to WebP

One of the most useful conversions is PNG to WebP for graphics with transparent backgrounds — logos, icons, product cutouts. WebP keeps the alpha channel in both lossy and lossless modes, so a transparent PNG often becomes a WebP at half the size with identical edges.

Use quality 85+ or lossless for transparency, since compression artifacts show most along the transparent edge. And never convert a transparent PNG to JPG by accident — with no alpha channel, the transparency gets filled in, usually with black or white.

Batch conversion and browser support

Converting one image is nice; converting two hundred is the real use case. Add a whole folder, pick WebP once, and download the results as a ZIP — every file keeps its original name with a .webp extension.

On support: WebP opens in all current versions of Chrome, Edge, Firefox, Safari (14+), and Opera, plus Android and iOS apps built in the last several years. If you serve images to the public web, WebP is safe as the default; keep a JPG copy only for legacy systems you specifically know about, such as old print pipelines.

Mistakes to avoid when converting to WebP

• Converting an already-tiny JPG and expecting miracles. If the source is a heavily compressed 60 KB JPG, the WebP will be small too — but it cannot recover detail that is already gone. Convert from the best-quality original you have.
• Using lossy settings for text-heavy graphics. Artifacts cluster around sharp edges. Screenshots and graphics with words deserve 90+ or lossless.
• Forgetting the animation. Converting an animated GIF to a still WebP keeps only one frame. If you need the motion, export as animated WebP instead.

Frequently asked questions

Is WebP better than JPG?

For file size at the same visual quality, yes — usually 25–35% smaller. JPG still wins on universal compatibility: every device and program from the last 30 years opens JPG, while WebP needs a reasonably modern browser or app.

Does WebP support transparency like PNG?

Yes. WebP has an alpha channel in both lossy and lossless modes, so transparent PNGs convert cleanly. Use quality 85+ or lossless to keep the transparent edges crisp.

Will my WebP images work everywhere?

In all modern browsers and most current apps, yes. Very old software — pre-2020 image editors, some print workflows — may not recognize WebP. For those cases, keep a JPG or PNG copy alongside.

Can I convert WebP back to JPG or PNG?

Yes, the tool converts both directions. Note that converting lossy WebP back to JPG recompresses the image, so do it from the WebP at high quality or, better, from your original source file.

Is the conversion private?

Completely. Conversion runs locally in your browser with no server upload, so your images never leave your device — there is no queue and no file-size limit imposed by a server.