Tide/moon phase/sunrise/sunset calculation

From the location and date, sunrise, sunset, moon phase (approximate) and tide (manual input) are displayed together.

Tides are displayed based on predicted/manually input data. The actual tide level changes depending on factors such as wind, atmospheric pressure, topography, and river inflow.

This tool does not replace safety judgment. Please be sure to check official information and local warnings when engaging in activities on the coast or in ports, and make decisions with safety as the top priority.

Other languages 日本語 | English | 简体中文 | Español | Português (Brasil) | Bahasa Indonesia | Français | हिन्दी | العربية

Presets and sharing

Inputs

time zone
tidal mode
Data acquisition (β) is currently in preparation. Please use manual input mode until publication.

Tidal events (up to 6 events)

Type Time (HH:MM) Tide level (m) Delete

Tidal events are automatically sorted and displayed in chronological order.

Results

sunrise/sunset

sunrise
sunset
photoperiod
condition

Moon age/moon phase

Moon phase
moon phase
Illuminance (approximate)

Moon age/moon phase is estimated using the average lunar model.

Astronomy tools

Find related tools for sunrise, twilight, moon phase, and observing planning.

Open astronomy hub

Tide (manual input)

Type time Tide level (m)
Maximum tide level
minimum tide level
Tidal difference (maximum-minimum)

The curve is not displayed because there are fewer than 2 tidal events.

Assumptions & limits

FAQ

Are the tide values accurate?

Since it is based on manual input or external forecast data, there may be differences from the actual tide level. Please be sure to follow official information and local warnings when making your final decision.

Why is the moon age different from other sites?

This tool uses a simple model. There may be differences from strict astronomical calculations.

What if data acquisition (β) cannot be used?

It may not be possible to obtain it due to regional restrictions or API restrictions. Please use the manual input mode by entering tidal events.

How to use Tide/moon phase/sunrise/sunset calculation effectively

What this calculator does

This page is for estimating outcomes by changing inputs in one controlled workflow. The model keeps your focus on variables, not output shape. Start with stable assumptions, then test sensitivity by changing one key input at a time to observe directional impact.

Input meaning and unit policy

Each input has an expected unit and a typical range. For reliable interpretation, check whether you are using the same unit system, period, and base assumptions across all runs. Unit mismatch is the most common source of unexpected drift in numeric results.

Use-case sequence

A practical sequence is: first run with defaults, then create a baseline log, then run one alternative scenario, and finally compare only the changed output metric. This sequence reduces cognitive load and prevents false pattern recognition in early experiments.

Common mistakes to avoid

Avoid changing too many variables at once, mixing incompatible data sources, and interpreting a one-time output without checking robustness. A single contradictory input can flip conclusions, so keep each experiment minimal and document assumptions as part of your note.

Interpretation guidance

Review both magnitude and direction. Direction tells you whether a strategy moves outcomes in the desired direction, while magnitude helps you judge practicality. If both agree, you can proceed; if not, rebuild the baseline and verify constraints before deciding.