How to convert WebP to JPG on iPhone
WebP is Google's image format, and it is now most of the web. That is why images you save from Chrome, Google Images or a modern website land in your Files app as .webp — and why some older app, form or piece of software then refuses to touch them.
What WebP is, and why you have one
WebP was released by Google in 2010. Its lossy mode is built on VP8 intra-frame coding (the same lineage as the VP8 video codec); its lossless mode is a separate, purpose-built algorithm. It supports an alpha channel and animation, and at comparable visual quality it is typically 25–35% smaller than JPG. That efficiency is why Google pushed it hard for the web and why sites serve it by default today.
You almost certainly did not choose WebP. It arrived because you long-pressed an image in a browser and saved it, or downloaded an asset, and the site's server decided WebP was the right format for your browser.
Why some apps still can't open it
iOS has been able to display WebP since iOS 14 — Safari, Photos and Quick Look all handle it. The problem is everything else: older desktop software, print shops, some upload forms, certain enterprise tools and plenty of third-party apps still have no WebP decoder. JPG has been universally readable for three decades. When something rejects your file, converting to JPG is the pragmatic fix.
This is a lossy-to-lossy re-encode. A lossy WebP is decoded to pixels, then re-compressed with JPEG. Generation loss applies: you are stacking a second lossy codec on top of the first. At a high quality setting it is hard to see, but it is real, and it gets worse every time you re-convert. Keep the WebP if you can.
Two things that will change
- Transparency is lost. WebP supports an alpha channel; JPG does not. If your WebP has transparent areas, Convexy flattens them onto a solid background — white by default, or a colour you choose in Options. If you need to keep the transparency, convert to PNG instead.
- The file will get bigger. JPG is the less efficient codec, so expect the JPG to be noticeably larger than the WebP at similar quality. You are paying in bytes for compatibility.
Animated WebP: if the file is an animated WebP, JPG has nowhere to put the animation — a JPG is one frame, full stop. Expect a single still image, not a moving one.
Why not just use a website?
Because a WebP-to-JPG website uploads your image to a server you know nothing about, converts it there, and asks you to trust a deletion policy you cannot verify. That is a poor trade for a file you could convert locally in a second.
Convexy decodes WebP with the decoder already built into iOS, re-encodes with Apple's ImageIO, and never opens a network connection. No account, no upload, no server. It works in Airplane Mode — the simplest possible proof that nothing is being sent anywhere.
How to do it
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Bring the WebP in
Tap Browse files and pick the .webp from Files or iCloud Drive, or share it into Convexy from the browser or another app.
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Choose JPG
Convexy only offers the formats this file can actually become — JPG, PNG, HEIC, TIFF, BMP, GIF, AVIF, ICO or PDF. Tap JPG.
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Pick a background if the image is transparent
JPG cannot store an alpha channel. Transparent pixels are flattened onto white unless you set a different background colour in Options.
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Set the quality
Keep it high — you are already re-encoding a lossy image, so there is no sense compounding the loss to save a few kilobytes.
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Convert, then save or share
Check the size comparison on the result screen, then save to Photos or Files, rename it, or push it into another app.
Common questions
Why do images I save from the web come out as WebP?
Because the website served WebP. Most modern sites and CDNs check what your browser supports and send WebP or AVIF instead of JPG, because it is significantly smaller and loads faster. When you save the image, you save whatever the server actually sent — which is the WebP, not a JPG.
Can iPhone open WebP files at all?
Yes. Since iOS 14, Safari, Photos and Quick Look can all display WebP. What trips people up is other software further down the line — an old desktop app, a print service, a web form with a strict file-type check. If everything in your chain handles WebP, you do not need to convert at all.
Does converting WebP to JPG lose quality?
Yes. If the WebP was lossy (most are), you are decoding an already-compressed image and re-compressing it with a second lossy codec. That is generation loss. Use a high quality setting to keep it invisible, and avoid repeatedly converting the same image back and forth.
Will the JPG be smaller than the WebP?
Almost certainly not — expect it to be larger. WebP typically beats JPG by 25–35% at the same visual quality. You convert to JPG for compatibility, not for size. If size is what you are after, WebP is already the better format and you should keep it.
What happens to a transparent WebP?
The transparency is flattened onto a solid colour, because JPG has no alpha channel and cannot represent a transparent pixel. Convexy uses white by default and lets you choose another colour. If the transparency matters, convert to PNG instead — it keeps the alpha channel exactly.
Can Convexy convert an image to WebP as well?
Yes. That is less common than it sounds on iOS: Apple's ImageIO can read WebP but ships no WebP encoder, which is why most iPhone converters only go from WebP. Convexy bundles Google's own libwebp library to do the encoding, so JPG, PNG, HEIC and the other image formats can all be written out as WebP.