World Time is an offline, read-only MCP server that gives accurate time zone, holiday, and calendar answers for agents.
world_time — Get the current time in up to 20 places, or convert a local time from one place to many; accepts cities, countries, zones, abbreviations (PST), and offsets (UTC+4); flags DST-skipped or repeated times and reports offsets, abbreviations, and next clock change.
holidays — List public holidays for a country, state, or city for a year, or check whether a given date is a working day; covers 207 countries, can include bank/optional/observance days, and marks Islamic-calendar dates as estimates.
business_days — Add business days to a date (e.g. add: 10 or -5) or count business days to an end date, skipping the local weekend (e.g. Fri-Sat in Saudi Arabia) and public holidays, with an optional weekend override.
date_info — Get weekday, ISO week, day of year, and leap-year status for a date; also do date arithmetic (e.g. +1 month, P1Y2M with month-end clamping) and count days until another date.
meeting_slots — Find meeting windows inside everyone's working hours across time zones over up to 14 days, skipping weekends and holidays, or falling back to the closest fitting time.
Runs fully locally with no network call, no API key, and results in milliseconds; all tools are read-only, idempotent, and return compact JSON.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type @ followed by the MCP server name and your instructions, e.g., "@world-time-mcp Find a meeting time for New York and Tokyo teams next week."
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
Time and calendar answers agents get wrong. Language models do date arithmetic from memory: they put London one hour off in the weeks when the US has changed its clocks and the UK has not, convert a time that a daylight-saving change skips, count Christmas as a working day, or put Saudi Arabia's weekend on Saturday and Sunday. World Time answers from the time zone database built into Node and holiday rules for 207 countries and their states:
Places the way people write them: "Portland, Maine", "Munich", "Japan", "PST", "UTC+5:30" or "America/New_York". Every answer names the zone it used; a country with several offsets says so.
Daylight saving handled, not guessed: a local time that a spring-forward change skips, or a fall-back change repeats, is flagged with both readings. "EST" written in July is noted as EDT.
Holidays and business days: public holidays by country, state or city, substitute days, multi-day holidays one row per day, each country's own weekend (Friday and Saturday in Saudi Arabia), and business-day counts that list what they skipped.
Meetings across zones: windows inside everyone's working hours over up to two weeks, skipping each person's weekend and holidays, or the closest time when nothing fits.
Everything runs locally: no network call, no key, answers in milliseconds. Holidays on the Islamic
calendar are astronomical estimates (the official day follows a moon sighting and can move by one)
and are marked estimated.
Built and maintained by Arhan Canli.
Needs Node.js 20 or newer. No account or key.
Claude Code
claude mcp add world-time -- npx -y world-time-mcpClaude Desktop: download world-time-mcp-<version>.mcpb from the latest release and open it. The bundle is signed; verify it with gh attestation verify <file> --repo arhancanli/world-time-mcp.
Any other client (Windsurf, Zed, Cline, Continue and others), in its MCP config file:
{
"mcpServers": {
"world-time": {
"command": "npx",
"args": [
"-y",
"world-time-mcp"
]
}
}
}Docker
docker build -t world-time-mcp https://github.com/arhancanli/world-time-mcp.git && docker run -i --rm world-time-mcpHosted (Streamable HTTP): node src/server.mjs --http serves stateless MCP at POST /mcp (port from PORT, default 3000).
Related MCP server: chuk-mcp-time
An agent calls world_time with:
{
"places": [
"London",
"Dubai"
],
"time": "2026-03-08 02:30",
"from": "New York"
}and gets back (recorded from the live server on 2026-09-26):
{
"utc": "2026-03-08 07:30",
"from": {
"place": "New York, US",
"zone": "America/New_York",
"date": "2026-03-08",
"time": "03:30",
"weekday": "Sunday",
"utc_offset": "-04:00",
"dst": true,
"abbreviation": "EDT"
},
"status": "skipped",
"note": "02:30 does not exist in New York, US on 2026-03-08: clocks jump forward past it. Converted 03:30, the time a clock shows at that moment.",
"results": [
{
"place": "London, GB",
"zone": "Europe/London",
"date": "2026-03-08",
"time": "07:30",
"weekday": "Sunday",
"utc_offset": "+00:00",
"dst": false,
"abbreviation": "GMT",
"next_change": "2026-03-29 01:00 to +01:00"
},
{
"place": "Dubai, AE",
"zone": "Asia/Dubai",
"date": "2026-03-08",
"time": "11:30",
"weekday": "Sunday",
"utc_offset": "+04:00",
"dst": false,
"abbreviation": "GST"
}
]
}Tool | What it does |
| Adds business days to a date (add: 10 or -5) or counts them to an end date, skipping the local weekend (Fri-Sat in Saudi Arabia) and public holidays. |
| Weekday, ISO week, day of year and leap year of a date ('today' = UTC); optionally the date after adding '+1 month' (month ends clamp) and the days until another date. |
| Holidays of a country, state or city for a year, or whether one date is a working day, with the next holidays. 207 countries; Islamic-calendar dates are estimates. |
| Use for any meeting across time zones: windows inside everyone's working hours (09:00-17:00 unless given) over up to 14 days, skipping weekends and holidays, else the closest time. |
| Time now in up to 20 places, or a local time in |
Offline and read-only: no network call at all (factory.allowHosts is empty), nothing written,
nothing logged except unexpected failures (to stderr, without your inputs).
Time zones come from the ICU database inside Node, so they are as current as your Node release.
Business days: the start date is never counted when adding (1 business day after Friday is Monday); when counting between two dates, both ends count if they are working days. A holiday that starts in the afternoon (Christmas Eve from 14:00 in Germany) leaves the day a working day and is noted.
Weekends come from the Unicode CLDR week data; pass weekend to override one.
Results are compact JSON with a matching output schema.
Measured 2026-09-26 with gpt-5.4-mini, 13 fixed tasks graded by fixed checks (bench/tasks.json, raw results in bench/results/).
Server | Correct | Input tokens | Output tokens | Tool calls | Median time |
This server | 13/13 | 24880 | 573 | 14 | 1.9 s |
mcp-server-time, the official reference time server | 8/13 | 9843 | 565 | 15 | 1.7 s |
Measured 2026-09-26 from Dubai, home connection against the live upstream, Node 24.19.0 (bench/perf.json, scripts/perf.mjs in the factory).
Call | First call | Repeat | Result size |
world_time: now in 5 places (city, ambiguous city, country, abbreviation, offset) | 7 ms | 1.5 ms | 1,123 chars |
world_time: a time the spring-forward change skips | 5 ms | 0.6 ms | 718 chars |
holidays: Saudi Arabia 2026 (multi-day Eid, estimated) | 7 ms | 0.3 ms | 918 chars |
business_days: 5 business days in Saudi Arabia across Eid | 7 ms | 0.2 ms | 450 chars |
meeting_slots: New York, London, Berlin over Christmas | 27 ms | 8.2 ms | 400 chars |
date_info: Jan 31 plus one month, days to Christmas | 2 ms | 0.2 ms | 269 chars |
First call: a fresh server process, including the TLS connection and the upstream's own time. Repeat: the same call again, answered from the in-process cache, so it shows this server's own overhead.
Tool definitions the model reads on every turn (name, description, input schema): 2,924 characters, against 1,002 for mcp-server-time, the official reference time server. The full tool list, with the output schemas and annotations clients use to validate results, is 4,632 characters (1,208 for the alternative).
Time zones: the IANA time zone database, as shipped in Node's ICU.
Holidays: date-holidays (ISC; holiday data CC BY 3.0), rules for 207 countries and their states and regions.
Cities: city-timezones (MIT), about 7,300 cities with population, province and zone.
Weekends: Unicode CLDR week data, as shipped in Node.
Confirm holidays that matter legally with the official calendar: governments declare extra days off, and some holidays move.
Web Reader: Reads web pages and PDFs as clean Markdown: main content, the sections that answer a query.
Actions Check: Checks GitHub Actions workflows: outdated actions, old Node runtimes, retired runners, injection.
Citation Check: Verifies citations: finds fabricated or mismatched references and retractions, returns clean BibTeX.
Config Check: Validates config files against their official schemas: tsconfig, compose, workflows, 1,400+ more.
Contact Check: Validates and formats phone numbers, email addresses and postal addresses for any country.
Cron Check: Explains cron expressions, lists next run times in any time zone, converts between cron dialects.
Dockerfile Check: Checks Dockerfiles: build-breaking mistakes, base image tags that exist, digests, platforms, EOL.
Domain Health: Email and domain checks: SPF lookup limits, DKIM keys, DMARC, DNS records, registration expiry.
The whole collection, 12 more
MIT, Copyright (c) 2026 Arhan Canli.
Adds business days to a date (add: 10 or -5) or counts them to an end date, skipping the local weekend (Fri-Sat in Saudi Arabia) and public holidays.
Inputs: start (required), where (required), add, end, +1 more. Returns: start, region
Weekday, ISO week, day of year and leap year of a date ('today' = UTC); optionally the date after adding '+1 month' (month ends clamp) and the days until another date.
Inputs: date (required), add, until. Returns: date, weekday
Holidays of a country, state or city for a year, or whether one date is a working day, with the next holidays. 207 countries; Islamic-calendar dates are estimates.
Inputs: where (required), all, date, year. Returns: region, results
Use for any meeting across time zones: windows inside everyone's working hours (09:00-17:00 unless given) over up to 14 days, skipping weekends and holidays, else the closest time.
Inputs: date (required), people (required), days, minutes. Returns: slots
Time now in up to 20 places, or a local time in from converted to them ('2026-03-08 02:30', '9am'). Flags times DST skips or repeats; gives each place's offset and next clock change. Places: city, country, zone, PST, UTC+4.
Inputs: places (required), from, time. Returns: utc, results
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
Loading tool schema changelog…
Scored across 5 tools
Each tool has a clearly separate purpose: business-day arithmetic, calendar date properties, holiday lookup, meeting window scheduling, and time conversion. Even though several reference holidays/weekends, their operations are distinct and unlikely to be confused.
All tool names use lowercase snake_case with noun phrases like business_days, date_info, holidays, meeting_slots, world_time. The pattern is consistent throughout, with no camelCase or mixed verb styles.
With 5 tools, the server is well-scoped for a world-time and date utility. Each tool covers a meaningful, non-redundant capability, and the count is neither too thin nor bloated.
The surface covers the main time/date operations: current time, conversion, date properties, holidays, business days, and meeting scheduling. Minor gaps exist, such as precise duration between times or explicit timezone listing, but most workflows can be accomplished with the available tools.
Convert times between zones, find shared working hours and meeting slots, check DST changes.
Date/time math for agents: business days, holidays, time zones, cron, RRULE. 25 free calls/day.
Exchange rates, public holidays for 100+ countries, time zones and conversions
Business-day, SLA, cron and recurrence calculations — offline, holiday-aware, no network.
