What Is Moon Calendar?

Moon Calendar is an interactive tool that lets you track moon phases, moonrise and moonset times, and upcoming lunar events for any location in the world. Whether you're planning a night out under the stars, scheduling photography sessions, or simply curious about tonight's moon, this tool gives you everything you need at a glance.

Why Track the Moon?

The moon has fascinated humanity for thousands of years. Its phases influence tides, wildlife behavior, and even cultural traditions. Knowing the current moon phase and when the moon rises or sets can help with:

Night Photography

Plan shoots around full moons or dark skies during new moons for optimal lighting conditions.

Stargazing

Avoid bright moonlit nights for the best deep-sky observations and clearer views of stars.

Outdoor Activities

Know how much natural light you'll have after sunset for hiking, camping, or evening adventures.

Gardening

Some traditions align planting schedules with lunar phases for optimal growth.

Cultural Observances

Many holidays and festivals follow the lunar calendar across different cultures worldwide.

Accurate and Location-Aware

Moon Calendar calculates moonrise, moonset, and phase data based on your specific geographic coordinates. Simply select your country and state, or use GPS detection for precise results. The data updates instantly as you change locations or dates.

Location Precision: Moon times can vary by several minutes between nearby cities. For the most accurate results, always select your specific location rather than a general region.

Your Data Stays Private

All moon phase calculations happen in your browser:

No server processing — Astronomical calculations run locally using JavaScript
No tracking — Your location data is only stored in your browser's local storage
GPS is optional — You can manually select any location without sharing your coordinates

Table of Contents

1. What Is Moon Calendar?
2. How to Use Moon Calendar
3. Features
4. Frequently Asked Questions

How to Use Moon Calendar

Set Your Location

Accurate moon data depends on your location. You have two options:

Manual selection — Choose your country from the dropdown, then select your state or city. The searchable dropdowns support typing to quickly find your location.
GPS detection — Click the crosshairs button to automatically detect your location. The tool will find the nearest city in our database.

Auto-save feature: Your selected location is saved automatically, so you won't need to set it again on your next visit.

Choose a Date

By default, Moon Calendar shows data for today. To view a different date:

Use the left/right arrows to move one day at a time
Click the date field to open a calendar picker and jump to any date
Click "Tonight" to return to the current date

Explore Moon Data

Once your location and date are set, you'll see comprehensive moon information:

Moon Phase Hero

A large visual showing the current moon phase with its name, illumination percentage, moon age, and lunar calendar date

Moon Times

Moonrise, moonset, altitude, and azimuth for your location

Monthly Calendar

Browse the full month with mini moon icons on each day. Click any day to view its details. Lunar calendar dates are shown below each solar date.

Upcoming Events

See the next New Moon, Full Moon, and Quarter phases with countdown

Moon Details

Expand for advanced data including distance, parallactic angle, and phase angle

Navigating the Monthly Calendar

The monthly calendar shows a mini moon icon for each day. Days with special phases are highlighted:

Full Moon Days

Highlighted in gold for easy identification

New Moon Days

Highlighted in purple to mark the cycle start

Today

Has a distinct background for quick reference

Use the arrows next to the month title to navigate between months. Click any day to update all moon data to that date.

Features

Real-Time Moon Phase Visualization

See the current moon phase rendered as a high-quality SVG graphic. The visualization accurately reflects the illuminated portion of the moon, from a thin crescent to a bright full moon. The rendering uses precise astronomical calculations to show exactly how the moon appears tonight.

High-quality rendering: The SVG format ensures crisp, scalable moon visuals that look perfect on any screen size or resolution.

Eight Moon Phases

Moon Calendar identifies and names all eight phases of the lunar cycle:

New Moon

The moon is between the Earth and Sun, not visible from Earth

Waxing Crescent

A sliver of light appears on the right side

First Quarter

The right half is illuminated (50% visible)

Waxing Gibbous

More than half is lit, growing toward full

Full Moon

The entire face is illuminated (100% visible)

Waning Gibbous

Light begins to decrease from the right side

Last Quarter

The left half is illuminated (50% visible)

Waning Crescent

A thin sliver remains on the left before new moon

Moonrise and Moonset Times

Get precise moonrise and moonset times calculated for your exact location. The tool also shows the moon's current altitude above the horizon and its compass direction (azimuth).

Moonrise Time

Exact time when the moon appears above the horizon

Local time zone adjusted
Accounts for terrain elevation

Moonset Time

Exact time when the moon disappears below the horizon

Precise to the minute
Location-specific calculations

Altitude

Current height of the moon above the horizon in degrees

Real-time updates
Useful for photography planning

Azimuth

Compass direction where the moon appears (0° = North, 90° = East)

Helps locate the moon in the sky
Essential for observation planning

Interactive Monthly Calendar

Browse an entire month at a glance with a mini moon icon on each day showing that day's phase. The calendar highlights today's date, full moon days, and new moon days. Click any day to instantly view its full moon data. Lunar calendar dates are displayed alongside solar dates, with the first day of each lunar month specially marked.

Solar Calendar

Standard Dates

Based on Earth's orbit around the Sun
Fixed 365-day year
Commonly used worldwide

Lunar Calendar

Traditional Dates

Based on moon's phases
29.53-day lunar months
Used for cultural events

Upcoming Lunar Events

Never miss a lunar event. The Upcoming Events section shows the next occurrence of each major phase — New Moon, First Quarter, Full Moon, and Last Quarter — with the exact date and a countdown in days.

Smart countdown: The tool automatically calculates how many days remain until each major lunar event, helping you plan ahead for photography, stargazing, or cultural observances.

Detailed Moon Data

For astronomy enthusiasts, expand the Moon Details section to access advanced astronomical measurements:

Distance

How far the moon is from Earth in kilometers (varies between ~356,500 km and ~406,700 km)

Illumination

Exact percentage of the visible surface lit by the sun (0% to 100%)

Moon Age

Days since the last new moon (0 to 29.53 days in a complete cycle)

Parallactic Angle

The angle of the moon's bright limb relative to the horizon (useful for astrophotography)

Phase Angle

The angle between the sun, moon, and observer (determines illumination)

Lunar Calendar Integration

Moon Calendar includes lunar (traditional) calendar dates, displayed both in the Phase Hero section and throughout the monthly calendar grid. This is especially useful for cultural events, holidays, and traditions that follow the lunar calendar.

Many cultures worldwide use the lunar calendar for determining festival dates, agricultural activities, and religious observances. The lunar calendar provides a natural rhythm aligned with celestial cycles.
— Traditional Astronomical Practice

Location-Aware with GPS Support

Choose from a comprehensive database of countries and states worldwide, or let the tool detect your location via GPS. Searchable dropdowns with country flags make it easy to find any location. Your preference is saved for future visits.

Global Coverage

Comprehensive database of locations worldwide

All countries and major cities
Searchable with country flags
Type to find locations quickly

GPS Detection

Automatic location detection for convenience

One-click location finding
Finds nearest city in database
Completely optional feature

Dark Mode Support

Moon Calendar supports dark mode with carefully chosen colors that complement the lunar theme. All elements — from the moon SVG to calendar cells and text — adapt seamlessly to your preferred theme.

Eye-friendly design: Dark mode reduces eye strain during nighttime use, making it perfect for planning evening observations or late-night astronomy sessions.

Frequently Asked Questions

How accurate are the moon phase calculations?

Moon Calendar uses the SunCalc library, which implements well-established astronomical algorithms. The calculations are accurate to within minutes for moonrise/moonset times and fractions of a degree for position data.

Note: Results may vary slightly from official observatory data due to atmospheric refraction and local terrain effects. For professional astronomical work, consult official observatory sources.

Why do moonrise and moonset times change with my location?

The moon's position in the sky depends on where you are on Earth. Two cities just a few hundred kilometers apart can have moonrise times that differ by several minutes. That's why selecting your specific state or city gives the most accurate results.

Example: New York and Boston, despite being relatively close, can have moonrise times that differ by 5-10 minutes due to their different latitudes and longitudes.

What does the illumination percentage mean?

Illumination shows how much of the moon's visible surface is lit by the sun. At 0%, it's a New Moon (not visible). At 100%, it's a Full Moon. A 50% illumination corresponds to either the First Quarter or Last Quarter phase.

New Moon 0%

Quarter Moon 50%

Full Moon 100%

Why does the moon sometimes not rise or set?

In certain locations — particularly at high latitudes — the moon can remain above the horizon all day ("always up") or below the horizon all day ("always down"). This happens because the moon's orbit is tilted relative to the equator, similar to how the sun behaves near the poles.

High latitude effect: This phenomenon is most common in polar regions (above 60° latitude) and varies throughout the year based on the moon's orbital position.

What is the lunar calendar date shown?

The lunar calendar (also known as the traditional or agricultural calendar) is a date system based on the moon's phases. Many cultures use it for traditional holidays, festivals, and ceremonies. Moon Calendar shows the corresponding lunar day and month alongside each solar date.

Used in Chinese, Islamic, Hebrew, and other cultural calendars
Each month begins with a New Moon
Months are approximately 29.53 days long
Important for timing traditional festivals and observances

Do I need to enable GPS?

No. GPS is optional and only used if you click the location detection button. You can always manually select your country and state from the dropdowns. If you do use GPS, the coordinates are only stored locally in your browser.

Manual Selection

Full Control

No location permissions needed
Choose any location worldwide
Complete privacy

GPS Detection

Quick Setup

One-click detection
Automatic location finding
Data stays in browser

Does this work offline?

Once the page is loaded, most features work without an internet connection. Moon phase calculations happen entirely in your browser. However, changing your location requires loading geographic data from the server, which needs an internet connection.

Moon phase calculations work offline
Date navigation works offline
Previously selected location data is cached

Changing to a new location requires internet
GPS detection requires internet

What is Moon Age?

Moon Age is the number of days since the last New Moon. A complete lunar cycle (from New Moon to New Moon) takes approximately 29.53 days. So a Moon Age of 14.7 days means you're roughly at a Full Moon.

Moon Age	Phase	Illumination
0 days	New Moon	0%
7.4 days	First Quarter	50%
14.8 days	Full Moon	100%
22.1 days	Last Quarter	50%
29.5 days	New Moon (cycle repeats)	0%

What are Parallactic Angle and Phase Angle?

These are advanced astronomical measurements used primarily by astrophotographers and researchers:

Parallactic Angle

Describes the orientation of the moon's bright edge relative to the horizon. Essential for astrophotography to predict how the illuminated portion will appear in your frame.

Phase Angle

The angle between the sun, moon, and observer. This determines how much of the moon appears lit. A phase angle of 0° = Full Moon, 180° = New Moon.

For enthusiasts: While these measurements are technical, they provide valuable insights for planning lunar photography and understanding the geometry of Earth-Moon-Sun relationships.