@jdsalasc/solvejs-date

Zero-dependency date utilities for JavaScript and TypeScript.

Utilities

• formatDate, toIsoDate
• parseDateStrict, parseIsoDate, parseUnixTimestamp
• addDays, diffInDays
• startOfDay, endOfDay
• isLeapYear, daysInMonth

When to use this package

Use it when you need predictable date parsing/formatting, UTC-safe operations, and common date math without adding heavy dependencies.

Limitations and Constraints

• Formatting tokens are intentionally limited to a small practical set.
• Helpers operate in UTC-safe mode and avoid locale-calendar formatting features.
• For advanced timezone rules per region, integrate a dedicated timezone library.

Install

npm i @jdsalasc/solvejs-date

Quick example

import { parseDateStrict, addDays, toIsoDate } from "@jdsalasc/solvejs-date";

const d = parseDateStrict("2026-02-07", "YYYY-MM-DD");
const next = addDays(d!, 3);
toIsoDate(next); // "2026-02-10"

DST/Timezone matrix quick check

import { diffInDays, parseIsoDate } from "@jdsalasc/solvejs-date";

const usStart = parseIsoDate("2026-03-08T06:59:59.000Z");
const usEnd = parseIsoDate("2026-03-09T06:59:59.000Z");
const euStart = parseIsoDate("2026-03-29T00:59:59.000Z");
const euEnd = parseIsoDate("2026-03-30T00:59:59.000Z");

if (usStart && usEnd) diffInDays(usEnd, usStart); // 1
if (euStart && euEnd) diffInDays(euEnd, euStart); // 1