"This browser is missing a feature this tool needs"
The tool needs a browser feature, such as the built in video encoder, that this browser doesn't have.
Last updated October 2, 2026
Okaysize processes files on your device using modern browser features: WebCodecs for video and audio, OffscreenCanvas for images and Web Workers to keep the page responsive.
What to try
Update your browser to the latest version, or use a recent Chrome, Edge, Firefox or Safari. On iPhone and iPad, update iOS, because Safari updates come with it.
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