Shadow Color Generator

The shadow color generator derives a shadow tone from a base color by lowering its lightness while keeping the hue and saturation, then writes the CSS box-shadow declaration.

What is Shadow Color Generator?

The shadow color generator derives a shadow color from a base color and writes it out as a ready-to-paste declaration. Choose a base colour and the tool computes a darker version with the same hue and saturation, then writes out a box shadow using that colour at partial opacity. A preview shows a card floating on a background with the shadow applied, so the effect is visible rather than merely described, and the code panel carries the declaration with a copy button.

The tone is derived rather than chosen, and that is the point of the tool. A shadow in the same hue as the surface reads as light falling on a coloured object, whereas pure black at low opacity reads as a grey smudge — the difference is subtle at low opacity and obvious when the shadow is strong or large. Deriving the tone also means the shadow stays consistent as the base colour changes, which matters in a design system where several surfaces each need their own shadow and the relationship between them should not have to be re-decided each time.

The derivation lowers lightness by a fixed amount with a floor, so the result is a markedly darker version of the base without collapsing to black. Hue and saturation are untouched, which is what keeps a warm surface producing a warm shadow. Opacity is written into the declaration as an alpha channel on the hex value, at a fixed level — enough for the shadow to be visible on a light page without becoming a hard edge.

• The rest of the declaration is conventional and fixed: a vertical offset, a substantial blur and a negative spread.
• That combination is the standard recipe for a soft, natural-looking elevation.
• The negative spread is the detail most hand-written shadows miss — it pulls the shadow inwards so it does not bleed out sideways from under the element, which is what makes a card look lifted rather than sitting in a pool of grey.

Where this is useful is anywhere elevation is part of the design language: cards, dropdowns, modals, floating action buttons. Deriving each shadow from its own surface colour gives a set of elevations that share a structure while each staying in the right hue family, which is much harder to achieve by mixing a single grey shadow across surfaces of different colours. It also answers a specific question quickly: if the brief says the shadow should be tinted rather than neutral, this is where the tone comes from.

• Offsets, blur and spread are fixed, so only the colour is derived; the geometry has to be edited in the copied declaration.
• The floor on lightness means a very dark base produces a shadow barely darker than the surface, and dark surfaces usually want a shadow made from a lighter tone instead — the reverse of what this tool produces.
• There is no inset variant, no multi-layer shadow and no dark-mode counterpart; within those bounds it hands over a tinted drop shadow as an editable css shadow color declaration, with a colored box shadow already matched to the surface.

How to use Shadow Color Generator

1. Pick the base colour — normally the surface the element will sit on.
2. Check the preview to see how strong the derived tone looks in place.
3. Copy the box-shadow declaration and adjust the offsets or blur by hand if the elevation needs to differ.

When to use Shadow Color Generator vs related tools

Use this when a design wants tinted rather than neutral shadows, or when several surfaces each need an elevation that belongs to them. Use the neumorphism generator when the element should appear moulded out of its background rather than lifted above it. When the shadow's geometry needs to be yours rather than fixed, the box shadow color tool exposes offsets, blur and spread alongside the colour, and when the shadow belongs to type rather than to a surface, the text shadow color tool is the same idea one property over.

Privacy & Security

This tool runs entirely in your browser — no data ever leaves your device. There is no server round-trip, no upload, no logging, and no account required. Your input is processed locally using client-side JavaScript and is never stored, transmitted, or accessible to anyone else. When you close the tab, everything disappears.

Frequently asked questions about Shadow Color Generator