Pretext

Zero-Reflow Text Layout

Pure JavaScript multiline text measurement & layout without DOM reflow. Uses canvas measureText internally, caches widths, then does pure arithmetic for layout. Microsecond-fast layout calculations enable animations and interactions impossible with traditional CSS.

0μs
DOM Reflow
<1μs
Layout Calc
60fps
Smooth

Text Reflow Around Cursor

Move your cursor through the text — watch it flow around in real-time at 60fps

Tight Chat Bubbles

Left: CSS max-width (wasted space in red). Right: Pretext shrink-wrapped to perfection.

CSS max-width

Pretext optimized

Masonry Virtual Scroll

500+ cards with variable text. Heights predicted instantly, only visible cards rendered.

Rendered: 0 / 0 FPS: 60

Typographic ASCII Art

Proportional character widths aligned pixel-perfect using Pretext measurement.

Text Physics Playground

Click to make letters fall with gravity. Click again to explode and reassemble.

Multilingual Layout Tester

Type anything — Chinese, Arabic, Hebrew, emoji, mixed scripts. See real-time measurements.

Predicted Height:
Actual Height:
Line Count:
Accuracy: