How AetherCut Edits Video Entirely in Your Browser - Zero Server Uploads

Most video editors upload your footage the moment you start. Your raw clips move to a server you don't control, processed by infrastructure you can't audit. AetherCut works differently - and you can verify it yourself in under 60 seconds. Here's the full technical breakdown.

The Architecture: Why Nothing Leaves Your Device

AetherCut runs inside a browser tab. No install. No account required to start. Every processing operation - cutting, captioning, chroma key, export - executes locally using three browser APIs that have quietly made client-side video processing viable.

HTML5 Canvas API

The Canvas API is the rendering layer. Every frame you see in the AetherCut timeline is drawn to an off-screen canvas. Compositing, overlays, text, and visual effects are applied directly in-memory on your device. No frame data is serialized and sent over the wire.

WebCodecs API - H.264 Hardware-Accelerated Export

The WebCodecs API is what makes 5x realtime export possible. It gives JavaScript direct access to the browser's hardware video encoder - the same H.264 acceleration your GPU uses for everything else. Before WebCodecs, browser-based video export had to go through software encoders, which were slow and CPU-heavy. WebCodecs bypasses that entirely.

The practical result: a 60-second 1080p clip exports in roughly 10–12 seconds on a mid-range machine. The encoded output never touches a server - it writes directly to your local filesystem.