Free Bulk Image to WebP Converter
Short answer: Add up to 100 supported images, apply one WebP quality or size rule, review the output, and download the completed batch as one ZIP. Image bytes and filenames stay in the browser during conversion.
Bulk conversion is the main reason BatchWebP exists. Instead of uploading one image at a time, you can drop a queue of JPG, PNG, GIF, SVG, AVIF, ICO, or BMP files, choose one output rule, and download everything as a ZIP.
Best uses
Use this workflow before publishing ecommerce catalogs, blog image libraries, landing page assets, documentation screenshots, or prototype images. The queue view shows file-level status while the summary bar tracks original size, output size, and estimated savings.
Recommended settings
For most web publishing work, start with 80% quality and original dimensions. If images are oversized, use a 0.5 or 0.7 scale before lowering quality too far. For strict CMS upload limits, use the target KB option in the converter.
Measured browser results
These 12 results were produced on 2026-09-13 with Google Chrome 152.0.7977.83 on darwin 25.6.0 arm64, using WebP quality values 0.6, 0.8, 0.9. Negative byte change means the WebP output was smaller than the generated PNG source.
| Generated fixture group | Quality | PNG bytes | WebP bytes | Byte change | Source SHA-256 |
|---|---|---|---|---|---|
| photograph | 0.6 | 491,534 | 6,374 | -98.7% | c43dbb232857… |
| photograph | 0.8 | 491,534 | 8,452 | -98.28% | c43dbb232857… |
| photograph | 0.9 | 491,534 | 14,508 | -97.05% | c43dbb232857… |
| screenshot | 0.6 | 65,088 | 15,756 | -75.79% | 3cd6106bad0e… |
| screenshot | 0.8 | 65,088 | 18,972 | -70.85% | 3cd6106bad0e… |
| screenshot | 0.9 | 65,088 | 24,750 | -61.97% | 3cd6106bad0e… |
| transparent_graphic | 0.6 | 55,789 | 31,184 | -44.1% | d44c590594b7… |
| transparent_graphic | 0.8 | 55,789 | 33,228 | -40.44% | d44c590594b7… |
| transparent_graphic | 0.9 | 55,789 | 36,402 | -34.75% | d44c590594b7… |
| illustration | 0.6 | 21,087 | 5,598 | -73.45% | 49bd01a8c631… |
| illustration | 0.8 | 21,087 | 6,940 | -67.09% | 49bd01a8c631… |
| illustration | 0.9 | 21,087 | 8,824 | -58.15% | 49bd01a8c631… |
The test contains one generated fixture per group at three encoder quality values, so the percentages must not be generalized to real photo libraries or compared as a representative average. Quality values are encoder inputs, not perceptual-quality scores. Review visual quality separately. Download all results, hashes, settings and limitations.
Can I bulk convert PNG and JPG images together?
Yes. The main bulk converter accepts mixed JPG and PNG queues along with other supported formats. Use the dedicated bulk PNG to WebP converter when every source needs the same transparency-focused settings, or bulk convert JPG to WebP for photo-focused defaults.
Open the bulk converter or try JPG to WebP and PNG to WebP.