`dayKey`function

The day a moment falls on, in UTC or in the named IANA time zone.

Import it

import { dayKey } from "@johnmorrisdotca/tane";

Definition

function dayKey(at: Date, timeZone?: string): DayKey

Name	Type	Description
`at`	`Date`	The moment to read as a calendar day.
`timeZone` (optional)	`string`	The IANA time-zone name; UTC when omitted.

string

The day a moment falls on, in UTC or in the named IANA time zone.

import { dayKey } from "@johnmorrisdotca/tane";

console.log(dayKey(new Date("2026-10-11T03:00:00Z"), "America/Toronto"));

2026-10-10

What it prints (run when this page was built)

View source Edit on GitHubMade from the source of @johnmorrisdotca/tane 1.3.0.