@lacspace/market-clock

Is the market open right now? When does it next open or close? — a holiday-aware, timezone-correct trading clock.

Every trading app needs to answer "are we open?" correctly — accounting for weekends, holidays, pre-open sessions and the exchange's timezone. This does it in a few bytes. Ships with NSE / BSE presets (IST, no DST — so the offset is exact).

• 🟢 isOpen() · isPreOpen() · status() → "open" | "pre-open" | "closed"
• ⏭️ nextOpen() · nextClose() · msToOpen() · msToClose()
• 📅 Weekend + holiday aware · pre-open session support
• 🏦 NSE / BSE presets, or bring your own ExchangeSpec
• ⚡ Zero dependencies · 🌍 isomorphic · 📦 ESM + CJS · fully typed

Install

npm install @lacspace/market-clock      # or pnpm add / yarn add / bun add

Quick start

import { MarketClock, NSE } from "@lacspace/market-clock";

const nse = new MarketClock(NSE);

nse.isOpen();        // true / false, right now (IST-correct from any timezone)
nse.status();        // "open" | "pre-open" | "closed"
nse.isHoliday();     // is today an exchange holiday?

nse.nextOpen();      // Date — next session open
nse.nextClose();     // Date — next session close
nse.msToClose();     // ms remaining until close (0 if not open)

Build a live badge

const label = {
  open: "🟢 Market open",
  "pre-open": "🟡 Pre-open",
  closed: "🔴 Closed",
}[nse.status()];

if (nse.isOpen()) {
  const mins = Math.round(nse.msToClose() / 60000);
  console.log(`${label} · closes in ${mins} min`);
} else {
  console.log(`${label} · opens ${nse.nextOpen().toLocaleString()}`);
}

Custom exchange / your own holidays

import { MarketClock, NSE, createClock } from "@lacspace/market-clock";

// extend the built-in list
const nse = new MarketClock({ ...NSE, holidays: [...NSE.holidays, "2026-11-20"] });

// or a completely different exchange
const custom = createClock({
  name: "MyExchange",
  offsetMinutes: 0,              // minutes ahead of UTC (no-DST exchanges)
  preOpen: { open: "08:00", close: "08:15" },
  regular: { open: "08:15", close: "16:30" },
  weekend: [0, 6],              // Sun, Sat
  holidays: ["2026-12-25"],
});

ℹ️ Holiday lists follow the annual exchange circular and can shift year to year. The built-in NSE list covers nationally-fixed days reliably — verify and extend for full-year accuracy.

API

| Member | Returns | | --- | --- | | isOpen(at?) isPreOpen(at?) | boolean | | isHoliday(at?) isWeekend(at?) isTradingDay(at?) | boolean | | status(at?) | "open" \| "pre-open" \| "closed" | | nextOpen(from?) nextClose(from?) | Date | | msToOpen(at?) msToClose(at?) | number (ms) | | NSE BSE | ExchangeSpec presets |

The Lacspace StockKit

| Package | For | | --- | --- | | @lacspace/indicators | Technical indicators | | @lacspace/market | P&L, XIRR, brokerage & charges | | @lacspace/market-clock | Market hours & holidays (this package) | | @lacspace/paper-trade | Headless paper-trading engine |

Licensing

This package is free under the Lacspace Free Licence — MIT-equivalent freedoms. Use it in personal and commercial projects at no cost; just keep the notice.

Not every Lacspace package is free. We also offer Commercial (paid), Client-specific, and Private (proprietary) packages under separate terms. See the full Lacspace Licence Centre.

Part of the Lacspace ecosystem — 35 zero-dependency, isomorphic TypeScript packages.

All packages ↗ · npm org ↗ · Licence Centre ↗ · GitHub ↗