This page documents an OPTIMADE Unit Definition. See https://schemas.optimade.org/ for more information.

**ID: https://schemas.optimade.org/defs/v1.2/units/si/1970/accepted/day**

`day`

**Unit name:** day

**Latin symbol:** day

**Display symbol:** day

**Description:** A unit of time equal to 86 400 seconds, using the 1967 base SI units.

The day unit appears in the International System of Units (SI), 1st ed. (1970) defined as "1 d = 24 h = 86400 s".

- The International System of Units (SI), 1st ed. (1970) categorizes the unit as "Units in use with the International System."
- The International System of Units (SI), 7th ed. (1998) changes the categorization to "Non-SI units accepted for use with the International System."

**Resources:**

- Definition in the International System of Units (SI), 1st Edition
- Wikipedia article describing the unit

**JSON definition:**

```
{
"$id": "https://schemas.optimade.org/defs/v1.2/units/si/1970/accepted/day",
"$schema": "https://schemas.optimade.org/meta/v1.2/optimade/physical_unit_definition.json",
"title": "day",
"symbol": "day",
"display-symbol": "day",
"alternate-symbols": [
"d"
],
"description": "A unit of time equal to 86 400 seconds, using the 1967 base SI units.\n\nThe day unit appears in the International System of Units (SI), 1st ed. (1970) defined as \"1 d = 24 h = 86400 s\".\n\n- The International System of Units (SI), 1st ed. (1970) categorizes the unit as \"Units in use with the International System.\"\n- The International System of Units (SI), 7th ed. (1998) changes the categorization to \"Non-SI units accepted for use with the International System.\"",
"resources": [
{
"relation": "Definition in the International System of Units (SI), 1st Edition",
"resource-id": "https://www.bipm.org/en/publications/si-brochure"
},
{
"relation": "Wikipedia article describing the unit",
"resource-id": "https://en.wikipedia.org/wiki/Day"
}
],
"defining-relation": {
"base-units": [
{
"symbol": "s",
"id": "https://schemas.optimade.org/defs/v1.2/units/si/1960/base/second"
}
],
"base-units-expression": "s",
"scale": {
"numerator": 86400
}
},
"x-optimade-definition": {
"label": "day_si_1970_accepted",
"kind": "unit",
"format": "1.2",
"version": "1.2.0",
"name": "day"
}
}
```