How to Convert Images to WebP / PhotoScape X and Online Tools
You can convert JPG or PNG images to WebP with PhotoScape X's batch saving tools or a browser-based converter. Keep the originals, choose suitable dimensions and compression, then check clarity, file size, and transparency before publishing. Renaming a file with a .webp extension does not convert its format.
What changes when an image becomes WebP?
WebP supports lossy compression, which discards some image information, and lossless compression, which preserves pixel information. It also supports transparency. It can make photographs and explanatory images smaller, but not every conversion reduces size. Saving an already heavily compressed JPG at high quality or in lossless mode can produce a larger file. Google's WebP FAQ explains these cases.
Resizing changes pixel dimensions; compression reduces file size; format conversion changes JPG or PNG into WebP. These are separate decisions. A 5,000-pixel-wide photograph displayed in a narrow article may also need resizing. A screenshot intended for enlarged reading, however, can become illegible if reduced too aggressively.
Prepare originals and an output folder
- Keep the source: use separate original and converted folders and avoid overwriting. Converting a lossy image back to PNG does not restore discarded detail.
- Identify the content: distinguish photographs, screenshots with small text, and transparent graphics. An ordinary still-image conversion may flatten animation; check animation support separately.
- Choose dimensions: consider article width and whether readers need to enlarge the image. Test one file before running a batch.
- Prepare to verify: check actual format, pixel dimensions, and file size. Showing filename extensions in Windows Explorer also helps reveal accidental double extensions.
Save a batch as WebP in PhotoScape X
On Windows, use the PhotoScape X Microsoft Store listing and check the publisher, Mooii Tech. Distinguish the basic app from Pro and in-app purchases, and check requirements for your device. The workflow below uses the batch-saving controls; positions and labels can vary with operating system, language, and version.
- Open PhotoScape X and select Batch.
- Choose your source folder and drag the required images into the workspace. Start with one file and check that unwanted resizing or filters are not enabled.
- Apply any intended size changes and click Save.
- Select WEBP as the output format and configure its quality controls. Do not confuse the WebP setting with a separate JPEG-quality tab.
- Choose a different subfolder or specified destination. Review the naming rule and handling of duplicate files.
- Review metadata retention before publishing photographs. EXIF or GPS data may contain camera or location information. If removing metadata, also check that colours remain suitable for the intended use.
- Confirm saving, then open the result from the destination folder. Only apply the same settings to the remaining files after the first result looks correct.
If the output is missing, check the selected destination and filename rather than assuming it replaced the original. If WebP is absent from the format choices, confirm that you are using PhotoScape X and the relevant save dialog. A browser converter is an alternative when the installed app does not offer the required export.
Convert in the browser without installing an app
The JB FACTORY WebP Converter accepts PNG, JPG, JPEG, and BMP, offers a quality slider, and provides individual or ZIP downloads. The tool states that conversion runs in the browser. Other services may upload or retain files, so do not apply that statement to every online converter.
- Open the page and click Input Files or drag files into the drop area. Start with a single image when working with large photographs.
- Adjust Quality. Around 80–85 can be a starting point for ordinary photographs, followed by inspection; it is not a universal optimum.
- Click Start Conversion and wait for completion. Keep the tab open and avoid reloading during processing.
- Save individual results or choose Download All (ZIP). Extract a ZIP before opening and checking the WebP files.
Large files can require more device memory and processing time. If the browser stalls, reduce the batch size or use a desktop application. For sensitive material, check the tool's processing and privacy terms first, or choose a local workflow without network transfer.
Choose quality by the result, not the number alone
Quality 80 does not mean “retain 80% of the original information.” The scale and output vary across tools and compression modes. Start photographs around 80–85 and inspect hair, foliage, gradients, and other fine detail. Small text, tables, and diagrams may justify higher quality or lossless output. Automatically saving every screenshot at low quality can damage letter edges and colour boundaries.
Quality 100 does not universally mean lossless either. Google's cwebp documentation distinguishes the lossy quality setting from lossless mode. If lossless output is required, check for an explicit option rather than assuming that moving a slider to its maximum has the same effect.
The table below checks the existing 1,672 × 941-pixel sample files attached to this article. One KiB is 1,024 bytes. This is an inspection of those files, rather than a newly reproduced conversion experiment; the quality values recorded in their filenames are distinguished from their actual compression types.
| Existing sample | Actual format | File size |
|---|---|---|
| Original PNG | PNG | 1,607,084 bytes · about 1,569.4 KiB |
| WebP with 100 in its filename | Lossless WebP | 1,233,886 bytes · about 1,205.0 KiB |
| WebP with 90 in its filename | Lossy WebP | 105,818 bytes · about 103.3 KiB |
| WebP with 80 in its filename | Lossy WebP | 64,646 bytes · about 63.1 KiB |
The compression mode also differs in this example. It does not show that reducing a slider from 100 to 90 will produce the same size change for every image. Open the original PNG, lossless WebP, or 90-labelled WebP to compare with the 80-labelled sample below.
Scaling an entire image to fit the screen can hide damage. Check both the intended display size and a 100% view, then choose a smaller file that remains clear enough for its purpose. If it looks blurred, return to the original and adjust dimensions or quality. Repeatedly compressing an already degraded conversion will not recover the missing detail.
Check the converted file on your blog
- File properties: verify that the actual format is WebP and that dimensions and orientation are correct. Re-export files that merely have a changed extension or cannot be opened.
- Appearance: inspect text, edges, photographic detail, and colours. Check transparent edges against both light and dark backgrounds.
- Upload: confirm that the WordPress media preview and generated sizes work. Support depends on the version, browser, and image-processing path. If uploads fail, review media information under Tools → Site Health and contact your host where needed.
- Published page: check desktop and mobile. After replacing existing images, clear relevant caches; the browser's Network tools can confirm the format and size actually delivered.
WordPress introduced WebP support in 5.8; 7.1 also uses client-side image processing in supporting browsers. Do not assume the same conditions as a server-only workflow: test uploads and thumbnails on the actual site. For automatic conversion and management of multiple sizes, see the WordPress image optimization plugin comparison.
