The publisher's conversion: iPhone camera to fast web page
This specific conversion exists for people who publish. You shoot on an iPhone, which produces HEIC, and you publish to the web, where WebP is the performance-safe default that every browser accepts. Uploading a HEIC to most CMSs fails outright; uploading a JPG works but ships more bytes than necessary. WebP at 80 to 85% quality is the sweet spot: visually clean, small enough to keep your Largest Contentful Paint fast, and accepted by WordPress, Ghost and every modern CDN.
Choosing the quality setting
The quality slider maps directly to the WebP encoder. For photographic content, 80 to 85% is indistinguishable from the original in normal viewing and roughly a third smaller than the same photo as JPG. Below 70% you start to see smoothing in skies and skin gradients. For images with text or sharp UI edges, push to 90 to 95%, or use HEIC to PNG if the image must be exact. On Safari the WebP encoding itself runs through a WebAssembly build of Google's libwebp, because Safari cannot encode WebP natively; Chrome and Firefox use the browser's built-in encoder. Either way it happens on your device.
Common questions
Why convert HEIC to WebP instead of JPG?+−
WebP produces files roughly 25 to 34% smaller than JPG at equivalent visual quality, and every modern browser has supported it since 2020. If the destination is your own website or blog, WebP loads faster and costs less bandwidth. If the destination is an upload form or another person, JPG remains the safer universal choice.
How much smaller will my photos get?+−
Compared with the JPG equivalent, expect 25 to 35% savings at the same visual quality. Compared with the original HEIC, WebP at 85% quality usually lands within a similar size range, since both formats use modern compression.
Does WebP keep transparency?+−
Yes. WebP supports alpha channels, so transparent HEIC content such as iPhone subject cutouts survives conversion. Unlike PNG, WebP compresses that transparency efficiently.
Which programs can open WebP files?+−
All modern browsers, plus recent versions of Photoshop, GIMP, Affinity and most image viewers. Older desktop software and some upload forms still reject it; when in doubt about compatibility, use JPG instead.