What order do the colors appear in?

The strip sweeps hue from 0 degrees (red) at the left edge through the full 360-degree color wheel back toward red at the right edge, following standard HSL hue order.

Why does every pixel in a column look the same?

Hue is computed once per column based on its x position, then applied to every pixel in that column, producing clean vertical color bands rather than per-pixel noise.

Can I make the strip taller without changing the colors?

Yes, height only affects how tall the bands are; the hue sweep is entirely a function of the x position and width.

Is this the same as a color picker gradient?

It's similar in spirit to the hue slider found in many color pickers, rendered as a full standalone image rather than a UI control.

Color Spectrum PNG Creator - Full Rainbow Strip Generator

Overview

Introduction

This tool creates a clean, full-width rainbow spectrum strip PNG, sweeping through every hue on the color wheel from left to right.

It's generated entirely in your browser by computing each column's hue directly from its horizontal position.

What Is Color Spectrum PNG Creator?

A pure pixel generator that assigns each column of the output canvas a hue proportional to its x position (0 degrees at the left edge, approaching 360 degrees at the right), at fixed full saturation and mid lightness.

Every pixel within a column shares that column's color, producing clean vertical bands rather than a per-pixel pattern.

How Color Spectrum PNG Creator Works

For each x coordinate, hue is computed as (x divided by width) times 360 degrees, then converted from HSL to RGB using fixed 100% saturation and 50% lightness.

That RGB color is then written into every pixel in that column, from y=0 to the bottom of the canvas, at full opacity.

When To Use Color Spectrum PNG Creator

Use it whenever you need a reference rainbow strip: for color-picker UI mockups, educational diagrams about hue, or decorative rainbow banners.

It's also a handy visual reference for spotting where a specific hue value falls along the 0-360 degree range.

Often used alongside Colorful PNG Generator and Multi-color Gradient PNG Creator.

Features

Advantages

Produces a mathematically exact, evenly-distributed hue sweep with no banding artifacts.
Any width and height up to 4096 pixels are supported, from a thin strip to a large poster-sized spectrum.
Runs entirely client-side with no external image assets needed.

Limitations

Only sweeps hue; saturation and lightness are fixed, so it won't produce pastel or dark spectrum variants.
The sweep is always left-to-right; there's no option for a vertical or radial spectrum layout.

Examples

Wide reference strip

Input

width=720, height=60

Output

A 720x60 PNG showing a smooth rainbow sweep from red through violet back toward red

A wider canvas gives finer hue resolution since more distinct x positions map to more distinct hues.

Thin color bar

Input

width=360, height=10

Output

A 360x10 PNG where each column's x position corresponds directly to one degree of hue

With width equal to 360, each column represents exactly one whole hue degree.

Best Practices & Notes

Best Practices

Use a width of 360 or a multiple of it if you want each column to map to a clean whole-degree hue value.
Pick a modest height (tens of pixels) for a strip meant as a UI reference bar; use a larger height for a standalone decorative image.

Developer Notes

The hue-per-column and HSL-to-RGB conversion logic lives in a pure, DOM-free lib function operating on a plain pixel buffer, independently unit-testable; only the component paints the resulting buffer onto a <canvas> for preview and download.

Color Spectrum PNG Creator Use Cases

Creating a reference rainbow strip for color-picker UI design
Generating a decorative full-spectrum banner
Producing an educational diagram of the hue color wheel

Common Mistakes

Expecting saturation or lightness to vary across the strip — only hue changes; the other two channels are fixed.
Requesting a very narrow width and expecting a smooth gradient — narrow widths produce visibly stepped hue bands.

Tips

Pair with the Color Step Generator to pull out a handful of discrete colors sampled from the spectrum.
Use a tall, narrow strip as a vertical hue reference if you rotate the downloaded image afterward.

Color Spectrum PNG Creator