About DevCraft
A high-performance CSS unit conversion suite engineered for web designers, frontend developers, and design systems.
Instant Calculations
Lightweight client-side engine with zero network roundtrips for real-time reactivity as you type.
Precision Formatted
Eliminates floating-point anomalies (e.g. 1.6000000000000001) while trimming redundant trailing zeros.
Next.js API Route
A standard HTTP endpoint for programmatic conversions and server-side automation.
Programmatic API: POST /api/convert
Integrate unit conversions into build scripts, IDE extensions, or workflows.
Example Request (cURL)
curl -X POST https://devcraft.dev/api/convert \
-H "Content-Type: application/json" \
-d '{
"value": 1.5,
"from": "rem",
"to": "px",
"rootFontSize": 16
}'JSON Request Body Payload
{
"value": 1.5, // (Required) Number to convert
"from": "rem", // (Required) Source unit
"to": "px", // (Required) Target unit
"rootFontSize": 16, // (Optional, default: 16) Root font size in px
"contextFontSize": 16, // (Optional, default: 16) Parent font size for em
"viewportWidth": 1440, // (Optional, default: 1440) Viewport width in px
"viewportHeight": 900, // (Optional, default: 900) Viewport height in px
"referenceValue": 1000, // (Optional, default: 1000) Base context for %
"precision": 4 // (Optional, default: 4) Max decimal places
}JSON Success Response (200 OK)
{
"input": {
"value": 1.5,
"unit": "rem"
},
"result": {
"value": 24,
"unit": "px",
"formatted": "24"
},
"explanation": "1.5rem × 16px (root font size) = 24px"
}