6 JavaScript Image Comparison Sliders

by Vladimir 2 min read

JavaScript image comparison sliders aren’t just widgets; they’re an effective way to visualize “before and after” image differences in real-time. The core technical aspect involves using CSS Masking or Clip-Path combined with JS logic for precise divider positioning. Many modern demos utilize CSS Custom Properties (CSS Variables) for dynamic control over slider and gradient styling. Explore this collection to implement a performant, clean, and touch-friendly comparison slider.

Examples

Before and after sneaker image comparison with a smooth interactive clip-path reveal effect driven by mouse tracking

Interactive Clip-Path Image Comparison

This is an Interactive Clip-Path Image Comparison. It juxtaposes two states of a single subject using a fluid, pointer-driven mask. Its function is to provide immediate, tangible proof of transformation (before/after), replacing static side-by-side galleries with a unified exploratory experience.

Technologies:
HTML SCSS JavaScript
Difficulty:Intermediate
Browser Support (as of Apr 2026):
Chrome Chrome 75+ Edge Edge 79+ Firefox Firefox 71+ Safari Safari 13+
Features:
Lerp InterpolationClip-Path MaskPointer Events
Code by: Juan Fuentes Juan Fuentes
License: MIT
Image Compare Viewer

Image Compare Viewer

A comprehensive documentation page featuring a complex, interactive Image Comparison Slider managed by the external ImageCompareViewer library.

See the Pen Image Compare Viewer.

Image Hover Effect

Image Hover Effect

A unique, visually impressive effect where the user moves a “liquid,” morphing lens to compare two scenes, demonstrating advanced use of SVG and DOM manipulation for visual UX.

See the Pen Image Hover Effect.

Original vs. Negative Card (Hover and Drag)

Original vs. Negative Card (Hover and Drag)

A tactile 3D comparison card where the slider reveals image states via blend modes, with smart label occlusion logic.

Vertical Original vs. Negative Card (Hover and Drag)

Vertical Original vs. Negative Card (Hover and Drag)

An interactive card that reveals a negative version of the image on hover, with a draggable slider to compare the two versions, utilizing CSS blend modes and 3D transforms.

Complementaries - Interactive Palette Picker

Complementaries - Interactive Palette Picker

A dynamic split-slider built with pure CSS and JS, utilizing CSS variables for custom slider and gradient styling, alongside masking for image visual division.