cd /news/developer-tools/show-hn-virtual-time-engine-to-recor… · home topics developer-tools article
[ARTICLE · art-74253] src=zlvox.com ↗ pub= topic=developer-tools verified=true sentiment=↑ positive

Show HN: Virtual time engine to record HTML to 60fps MP4, no drops

A new tool called Virtual Time Engine lets users record HTML, CSS, and JS animations as 60fps MP4 or WebM videos entirely client-side using the WebCodecs API, with no uploads, sign-ups, or watermarks. The engine overrides browser timing functions to ensure consistent frame capture regardless of machine speed, supporting resolutions up to 4K and external libraries like Three.js and GSAP. It is free and unlimited, but requires Chrome 94+, Edge 94+, or Brave on desktop for recording.

read1 min views1 publishedJul 26, 2026
Show HN: Virtual time engine to record HTML to 60fps MP4, no drops
Image: source

Write HTML, CSS & JS animations — export as MP4 or WebM instantly. 100% client-side via WebCodecs API. Zero uploads, zero sign-up, zero watermarks.

You write HTML, CSS and JS animations in the editor. The Virtual Time engine freezes browser time, steps it frame-by-frame, captures each frame onto a canvas, then encodes them using the browser-native WebCodecs API. No server involved at any point.

Recording requires the WebCodecs API — available in Chrome 94+, Edge 94+, and Brave on desktop. Firefox and Safari do not yet support VideoEncoder

. The editor and live preview work on all modern browsers regardless.

Export as WebM (VP9) or MP4 (H.264). MP4 is best for Instagram, TikTok and YouTube. WebM is best for web embedding. Resolutions available are 720p, 1080p, and 4K. Frame rates go up to 60fps with configurable quality levels. Completely free. No watermarks, no sign-up, no limits. Record as many videos as you want at any resolution. Your output contains only what you put in the editor — nothing else is added.

Normal screen recorders capture whatever frames your GPU renders in real time — resulting in dropped frames on slow machines. The Virtual Time engine overrides Date.now()

, requestAnimationFrame

, and setTimeout

so every frame is rendered at exactly the right moment, regardless of machine speed.

Yes. The editor supports any external resources via @import

in CSS (Google Fonts, etc.) and <script src> in HTML. Make sure resources are CORS-friendly. Libraries like Three.js, GSAP, and Canvas-based renderers all work well via the canvas-capture path.

── more in #developer-tools 4 stories · sorted by recency
── more on @virtual time engine 3 stories trending now
sponsored brought to you by zahid.host 4,200+ EU-deployed projects
reading about agents? ship yours in a single git push.

Run your AI side-project on zahid.host

EU-based hosting, git-push deploys, automatic HTTPS, no cold starts. Free tier with a custom domain — perfect for shipping the agent you just read about.

$git push zahid main
Live at https://your-agent.zahid.host
Get free account → Pricing
from €0/mo · no card required
LIVE [news/show-hn-virtual-time…] indexed:0 read:1min 2026-07-26 ·