Sailing theory
you can operate.
Drag a vessel through 360° and read her lights. Hear the actual sound signal, synthesised. Track CPA and TCPA on moving radar contacts. Built browser-native — nothing equivalent on the web.
ColRegs · Lights.
The signature simulator. Drag any of 18 vessel types through 360° and watch the lights an observer would see from every aspect. Click through for the rule reference.
Day shapes.
Hoist anchor balls, NUC cylinders, RAM cones. Correct order, correct height, every vessel type.
Sound signals.
Web-Audio synthesis — no MP3s, no licensing. Fog, manoeuvring, anchor, aground. Identify-the-signal quiz mode.
Radar.
Animated PPI scope. Five collision scenarios with real-time CPA + TCPA. Drag the EBL and VRM to bear.
Drop these on your own site.
Every simulator has a clean embed mode under /embed. Permissive iframe headers, minimal chrome, a small “by TideLab” footer. Free for non-commercial use.
Browse the embed gallery →Browser-native
No app store. No download. Mobile-friendly on every screen.
Web Audio synthesis
Sound signals are real waveforms, not MP3s. No licensing, infinite variations.
SVG diagrams
Crisp at any zoom. No bitmaps. Print at 300dpi if you really need to.
Matches the rules
Light positions and signal patterns follow ColRegs Annex I + III exactly.