Themes

Change InstaCalc's colors and typography.

InstaCalc ships with dozens of built-in themes. Each one changes the colors, fonts, and chrome across the whole app.

Open the theme picker from the bottom-right dock (desktop) or the bottom nav (mobile). Changes apply instantly.

What the panel groups

  • Light — for daytime
  • Dark — for long sessions
  • Bold — distinctive looks like Brutalist and 1984 Terminal

Where it applies

The theme is a personal preference. It’s saved in your browser and applies everywhere you go on the site — your calcs, the gallery, explore.

When you share a calc with someone, they see it in their own theme, not yours.

Embedding a themed calc

Any built-in theme can be applied to an embed via the ?theme=<name> query parameter on the canonical /<id>/embed URL. Drop the URL into an iframe on your own site and InstaCalc renders a fully-themed calculator — colors, fonts, and chrome baked in at first paint thanks to server-side rendering.

The same BMI calculator, four ways:

Daylight ?theme=daylight
/bmi-calculator/embed?theme=daylight
Night ?theme=night
/bmi-calculator/embed?theme=night
Brutalist ?theme=brutalist
/bmi-calculator/embed?theme=brutalist
1984 Terminal ?theme=1984
/bmi-calculator/embed?theme=1984

Swap bmi-calculator for any gallery slug (or shortid) and daylight for any built-in theme name (warm, morning, nordic, retro, grunge, cute, …). The theme- prefix is added automatically.

Custom themes

You can build your own. The theme panel has a Custom Colors option that opens a color picker for the background, ink, accent, and chrome. Pick what you want, save, and InstaCalc uses your custom theme everywhere.

You can also use a custom font on top of any theme — built-in or your own.