startOfQuarterForUnix

Signature

startOfQuarterForUnix(value: number, options?: { epochUnit?: "seconds" | "milliseconds"; timeZone?: string; disambiguation?: Disambiguation; offset?: Offset; }): number

import { startOfQuarterForUnix } from "@northguild/gmt/unix/calculate";

Return the start of the quarter for a Unix timestamp.

• Converts to ZonedDateTime, calculates quarter start, converts back to epoch.
• Q1 returns month 1, Q2 returns month 4, Q3 returns month 7, Q4 returns month 10.
• disambiguation controls DST gap/overlap resolution when the quarter-start boundary lands on an ambiguous local time: “compatible” (default, matches Temporal’s default), “earlier”, “later”, or “reject” (throws, resulting in null).
• offset controls whether the source’s existing UTC offset is kept when computing the new boundary: “prefer” (Temporal’s own default — keeps the source offset whenever still valid, which makes disambiguation inert in the (rare) common-zone case since quarter boundaries don’t fall on DST transitions), “use”, “ignore” (this function’s default — always recomputes from time zone + local time, discarding the stale offset), or “reject” (throws if the source offset is invalid for the new fields, independent of disambiguation). Leave offset at its default unless you specifically need Temporal’s raw .with() semantics.
• Returns null for invalid input.

Parameters

Parameter	Type	Description
value	number	Unix timestamp (number)

Options

options

Option	Type	Default
epochUnit?	"seconds" | "milliseconds"	—
timeZone?	string	—
disambiguation?	Disambiguation	—
offset?	Offset	—

Returns

Unix epoch number representing the start of the quarter, or null on invalid input

Related types

• Disambiguation
• Offset

Examples

startOfQuarterForUnix(1706659200000) // 1704067200000
startOfQuarterForUnix(-86400000) // -25598400001 (Q1 1969 starts Jan 1)

Source

unix/calculate/startOfQuarterForUnix.ts