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IntersectionObserver Playground - Live Visual Lab | IconVault

A real IntersectionObserver with threshold and rootMargin sliders, live ratio meter, scroll demo and callback log. Copy production code. Free.

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IntersectionObserver Playground

Threshold and rootMargin sliders with callback log

5 of 5 free uses left
0.50

Fraction of the target that must be visible before the callback fires.

Grows or shrinks the root's box. Try 200px to preload early, or -50px to demand a deeper entry.

Presets

live intersectionRatio0.00 - hidden

Red line = your threshold. Green bar = current ratio.

5 of 5 free copies left.

Live demo - scroll the box

scroll down
target
keep scrolling

Callback log (0)

Scroll the demo box. Every time the ratio crosses a sampled step, the real observer callback logs here.

About this tool

IconVault's IntersectionObserver Playground uses a real IntersectionObserver, not a simulation. Drag the threshold slider, type a rootMargin, then scroll the demo box and watch the live intersectionRatio meter move while every callback lands in a timestamped log with its ratio and visibility state.

Presets cover the classics: lazy images, half-visible reveals, fully-visible triggers and 200px early preloading. When the behavior feels right, copy the production-ready observer code with your exact settings. Everything is free and runs fully in your browser.

Frequently asked questions

Popular searches

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