What is the Ocean Viewing Index (OVI)?

The Ocean Viewing Index (OVI) is Seaidx’s 0–100 travel-planning score for how the coast is likely to look. It brings together six factors: color, clarity, visibility, sea state, lighting, and water quality. It is designed to answer a sightseeing question: is this a promising time to see the sea?

How is OVI calculated?

Seaidx combines modeled tide conditions, satellite-derived ocean-color signals, marine weather, and astronomical context. The six sub-indices are assessed together, with rainfall able to reduce the color component when conditions are likely to make water appear darker or less clear. The result is an explanatory viewing estimate, not a guarantee of a particular beach scene.

Is a tide timetable enough to plan ocean viewing?

Not by itself. Tide times are essential when an activity depends on water level, such as tide pools, exposed rocks, a sandbar, or beach access. They do not by themselves describe color, clarity, haze, wind-driven chop, cloud cover, or viewing light. For a scenic visit, read the tide timetable together with OVI and the local forecast.

Tide forecast versus an ocean viewing index: which should I use?

They answer different questions and work well together. A tide forecast helps you plan for high and low water at a specific time. An ocean viewing index helps you compare likely sightseeing conditions, including sea appearance and light. Use tide information first when timing depends on the shoreline; use OVI when choosing the day or time that is most promising for a coastal walk, photography, or sea viewing.

Can I use Seaidx for navigation or safety-critical decisions?

No. Seaidx is for travel planning and sightseeing context only. It is not a navigation aid and must not be used for boating, route planning, emergency decisions, or other safety-critical purposes. Always consult official marine forecasts, local warnings, and qualified local guidance before entering the water or going offshore.

About Seaidx and the Ocean Viewing Index

Seaidx helps coastal travelers decide whether a beach visit is likely to be rewarding for sea viewing. It pairs tide information with the Ocean Viewing Index (OVI), a 0–100 summary of the conditions that shape how the water and coastline may look.

A travel-planning tool for seeing the coast

A tide table answers an important but narrow question: when will the water be high or low? That matters for tide pools, sandbars, exposed rocks, shoreline walks, and beaches where access changes with the water level. For sightseeing, however, tide height is only part of the decision. A calm, clear, well-lit coastline can be much more appealing than a choppy or hazy one at the same tide.

Seaidx is built for the broader question: is the sea worth seeing today? OVI turns several viewing-related signals into a legible score while keeping tide times available alongside it. This makes it useful for coastal walks, beach photography, scenic drives, and choosing between flexible beach days. It is not a surfing forecast, a boating service, or a replacement for official safety information.

Start on the Seaidx homepage to explore current conditions, then open a location page for local tide times, an OVI forecast, and the factors behind the score. Our beach directory covers 183 coastal locations: 114 in Asia-Pacific and 69 in Europe.

How the Ocean Viewing Index works

OVI is a weighted, model-derived score from 0 to 100. It does not claim to reproduce every local view; rather, it gives travelers a consistent way to compare the factors that commonly influence whether the sea looks inviting. The score has six dimensions:

Color

Satellite-derived ocean-color signals help describe whether water is likely to appear vivid or muted.

Clarity

Turbidity and related signals help indicate how clear the water may look.

Visibility

Atmospheric visibility and sea-fog risk affect the distance and detail a visitor can see.

Sea State

Wind and wave conditions help distinguish calm water from a rough or choppy surface.

Lighting

Cloud cover and sun angle influence contrast, color, and the quality of a scenic view.

Water Quality

Chlorophyll anomalies and related indicators contribute context about changing coastal conditions.

Scores are grouped into five practical bands: 80+ Excellent, 65+ Good, 50+ Fair, 35+ Poor, and below 35 Bad. A higher score is a stronger signal for sightseeing conditions, but it should still be read with the location’s tide table, weather outlook, and any local advice.

Data inputs and method

Tides. Seaidx uses global tide models, including TPXO and FES sources, with harmonic-analysis fallback where needed to provide predicted high and low water.

Ocean color. Satellite ocean-color observations provide context for color, chlorophyll, and clarity-related signals.

Marine weather and light. Wind, wave, cloud, rainfall, and astronomical timing add the conditions that a tide chart alone cannot show.

When tide information matters most

Use tide times as the primary planning signal when you need a specific water level: a tide pool, a walk across a sandbar, a low-tide rock shelf, or a beach whose usable area changes through the day.

Use OVI to compare the likely quality of the view, then use the tide chart to choose a suitable time within that day. For the strongest plan, check both shortly before departure because local weather can change quickly.

For a practical walk-through, read our ocean viewing index and tide forecast guide.

Frequently asked questions

What is the Ocean Viewing Index (OVI)?: The Ocean Viewing Index (OVI) is Seaidx’s 0–100 travel-planning score for how the coast is likely to look. It brings together six factors: color, clarity, visibility, sea state, lighting, and water quality. It is designed to answer a sightseeing question: is this a promising time to see the sea?
How is OVI calculated?: Seaidx combines modeled tide conditions, satellite-derived ocean-color signals, marine weather, and astronomical context. The six sub-indices are assessed together, with rainfall able to reduce the color component when conditions are likely to make water appear darker or less clear. The result is an explanatory viewing estimate, not a guarantee of a particular beach scene.
Is a tide timetable enough to plan ocean viewing?: Not by itself. Tide times are essential when an activity depends on water level, such as tide pools, exposed rocks, a sandbar, or beach access. They do not by themselves describe color, clarity, haze, wind-driven chop, cloud cover, or viewing light. For a scenic visit, read the tide timetable together with OVI and the local forecast.
Tide forecast versus an ocean viewing index: which should I use?: They answer different questions and work well together. A tide forecast helps you plan for high and low water at a specific time. An ocean viewing index helps you compare likely sightseeing conditions, including sea appearance and light. Use tide information first when timing depends on the shoreline; use OVI when choosing the day or time that is most promising for a coastal walk, photography, or sea viewing.
Can I use Seaidx for navigation or safety-critical decisions?: No. Seaidx is for travel planning and sightseeing context only. It is not a navigation aid and must not be used for boating, route planning, emergency decisions, or other safety-critical purposes. Always consult official marine forecasts, local warnings, and qualified local guidance before entering the water or going offshore.

Who makes Seaidx?

Seaidx was founded by Citron Chan and is part of the VoyBird travel platform. The product is designed to make coastal conditions easier to understand without overstating what a forecast can promise.

Disclaimer

All values are model-derived estimates for travel planning only. Seaidx is not a navigation aid and must not be relied upon for safety-critical decisions. Always check official marine forecasts before entering the water.