You save a picture from a website, and it shows up on your iPhone as a .webp file. Then an upload form, an older program or someone else's computer won't take it. Many websites send their images as WebP, so this happens a lot. JPG (also written JPEG) is the format almost everything accepts. This guide explains what WebP is, then shows how to turn it into JPG with Convert Cat, our photo and PDF converter for iPhone and iPad.
What WebP is
WebP is an image format made for the web. Its main job is small files, so pages load faster. A WebP can be a photo, a graphic with a see-through background, or a short animation.
Your iPhone can read WebP images, which is why Convert Cat can open them. But not every app, website or program accepts WebP, and many forms ask for JPG or PNG. Converting gives you a file that opens almost anywhere.
Convert WebP to JPG, step by step
- Open Convert Cat. The first time, it asks What are you making? Tap Convert & PDFs. Next time it opens straight there.
- Pick your images. Tap Choose Files for WebP files saved in Files or iCloud Drive, or Choose Photos for images in your photo library. You can pick as many as you like, and mix WebP with other images.
- Tap Convert format ("To JPEG, PNG, HEIC, PDF and more").
- Check From and To. On the Convert screen, below the size panel, From shows WEBP. Under it, tap JPEG. The note below says "Opens everywhere." JPEG is already selected the first time you open the screen.
- Tap the button at the bottom, such as Convert 3 Photos, or Convert Photo for one.
On the result, tap Save to Photos, Save to Files or Share. Tap a file in the list to look at it before you send it.
You won't see the one-tap Convert to JPEG button for WebP files. That shortcut only appears when every file you picked is an iPhone photo (HEIC). For WebP, Convert format is the way in.
JPG or PNG: when transparency matters
JPEG can't store see-through pixels. Some WebP images, like logos and stickers, have a clear background. When you convert one of those to JPEG, Convert Cat fills the clear areas with white. A dark logo on a clear background comes out as a dark logo on white.
If the background has to stay clear, tap PNG instead of JPEG. PNG keeps transparency, but the note on screen warns: "PNG is lossless, so it's often bigger than the original."
Not sure which you have? Tap Keep. The note reads: "Each photo keeps its own format. WebP, AVIF, RAW and ICO become JPEG, or PNG if they're see-through." So a WebP photo becomes a JPEG, and a WebP with a clear background becomes a PNG.
For more on the PNG side, see how to convert PNG to JPG on iPhone.
Quality and file size
The first time, JPEG quality is 90%, labelled Best; after that, the Convert screen remembers your last settings. To change it, tap More options. Under File size, with Quality selected, move the slider. The label reads Best, High, Medium, Low or Smallest, and the panel at the top shows about how big the files will be.
A JPEG can come out bigger than the WebP it came from. When the estimate is clearly bigger, the Convert screen says so, for example "JPEG will be bigger than the original." The result says "This file is bigger than your original." Tap Make smaller instead and pick a size under Target size: 100 KB, 200 KB, 500 KB, 1 MB, 2 MB or 5 MB, or type your own next to Under.
More options also has Pixels, if you want a smaller width and height too. The walk-through is in how to resize a photo on iPhone.
File names and hidden photo info
Files you pick with Choose Files keep their names with a new ending, so banner.webp becomes banner.jpg. Images picked with Choose Photos come in as Photo 1, Photo 2 and so on. With Convert Cat Pro you can choose Name them under More options and set your own pattern.
Further down the Convert screen is Hidden photo info. Pick Remove location & photo info ("Recommended for sharing"), Remove location only, or Keep everything.
What Convert Cat doesn't do
- It can't save as WebP. iOS reads WebP but doesn't write it, so WebP isn't in the To list. Convert Cat saves JPEG, PNG, HEIC, TIFF, GIF, BMP or PDF.
- It doesn't keep animation. An animated WebP becomes a still image of its first frame.
- It doesn't download images. Save the WebP to Files or Photos first, then pick it in Convert Cat.
- It doesn't change your original. Convert Cat works on copies. Your WebP files in Photos and Files stay as they are.
What it costs
Converting WebP to JPG or PNG is free, for as many images as you pick, and so are quality, target size, resizing and removing photo info. There's no watermark, no ads, no subscription and no account. Convert Cat Pro is an optional one-time purchase. For converting, it adds four extras: Saved presets, Name your files, Shortcuts and Convert from the share sheet. The same purchase also adds extras to the app's Watermarks part. More on the Convert Cat page.
Quick answers
How do I convert WebP to JPG on iPhone?
In Convert Cat's Convert & PDFs, tap Choose Files or Choose Photos. Pick the WebP, tap Convert format, tap JPEG and tap the Convert button at the bottom.
Can I convert JPG to WebP?
No. iOS doesn't write WebP, so Convert Cat can't save one.
What happens to a transparent background?
JPEG has no transparency, so Convert Cat fills those areas with white. To keep the background clear, pick PNG or Keep.
Can I convert several WebP files at once?
Yes. Pick as many as you like; the button counts them, such as Convert 5 Photos.
Will my original WebP be deleted?
No. Convert Cat works on copies, so your originals are never changed.
Try Convert Cat
Try Convert Cat: free, no watermark, no sign-up → iyio.com/apps/convert-cat