Making a plan
What does Scan and Go do?
Plan smarter. Sail with confidence.
Scan and Go helps coastal sailors in the UK make better go/no-go decisions by showing when conditions are most favourable for a passage. Simply choose your departure and destination harbours, enter your usual boat speed, and the planner analyses tide, tidal streams, weather, and daylight conditions to identify the best departure windows over the next three days.
Designed primarily for UK coastal cruising, Scan and Go brings together information that would normally require multiple charts, forecasts, and tide tables, presenting it in one clear and practical view. AI-assisted analysis helps interpret the available data and highlight the conditions that matter most, allowing you to assess a passage more quickly and with greater confidence.
Whether you're planning a short hop between ports or a longer coastal passage, Scan and Go helps you make informed decisions before casting off.
Start planning your next passage today and discover the best time to leave.
How do I make a plan?
Type the harbour you leave and the harbour you are going to. Pick each one from the list so the name matches. Enter your average speed in knots. That is your speed through the water, not your speed over the ground. Then press Find My Best Departure Time.
What is the gust box for?
Leave it empty if you do not want a gust limit. If you type a number, hours where the forecast gust is that strong or stronger are left out.
What does “Daylight departures only” do?
Tick it and dark hours are left out. Only leaving times in daylight are shown.
Reading the colours
Why are there three days?
The planner looks at today and the next two days. Each row is one day. The time on the row is the quickest leaving time it found for that day at the speed you entered.
What does green mean?
Green means that leaving time is close to high water. Close means within an hour and a half before high water, or within an hour and a half after it. A tick on the day chip means the same thing. Green is a better tide window. It is not an order to sail.
What does amber mean?
Amber means take care. The time is in the slack just before low water.
What does red mean?
Red means a poor time, or a time that needs care. Often the tide is ebbing. A stronger red means the tide is ebbing, the wind is blowing onto the entrance, and there is swell. Check the words on that row before you decide.
What does grey mean?
Grey means none of the three days has a leaving time close to high water. The quickest hour that day sits outside that hour-and-a-half window. Grey is not a ban on the passage. Some harbours do not need high water to leave or enter. Read the note on the row.
What do the stars mean?
Stars score the tide at the chosen leaving time. Five is the best, close before high water. Four is still good, just after high water. Three is caution. Two is poor. One is the high-risk case. No stars means there is no strong tide window to score.
What is the “shortest time”?
It is the fastest of the three days at the speed you typed. The speed over the ground on the row includes the sea current. With the stream you arrive sooner. Against the stream you take longer.
Why is the return trip a different colour?
The two trips are not the same passage read backwards. The stream that helps one way holds the other up, so the quickest hour moves. The colour follows that hour. One way can land near high water. The other way can land away from it.
Map, tides, and sharing
What does the line on the map show?
It shows the shape of the passage around the coast. It is not a route to steer. Use your charts for the course.
What do the tide boxes show?
One box is for the harbour you leave. The other is for the harbour you arrive at. Each shows the high and low water nearest your time, the height difference, and whether that day is springs, neaps, or in between.
What if a harbour has no tide station?
The planner borrows the nearest harbour that does have one, and it says so. Those times belong to the nearby harbour, not to the exact entrance you typed.
What is the Why button?
Open Why on a day to read how that time was worked out: the tide, the weather, the sea current, and any harbour note. Close puts that detail away.
How do I print?
Open Why on the day you want. Print is there while that panel is open. You can include the map or leave it off.
How do I share the plan with crew?
Open Why on the day you want. Share with crew is there while that panel is open. It gives a link and a QR code for that day. Copy link puts that address on the clipboard. The crew page works the plan out again when it is opened, so the weather can change. Ask them to open it within 6 hours. After that, the page tells them to check with the person who sent it.
Can I use this to navigate?
No. This is a planning aid. Weather, tide, and current are forecasts and they change. Always check official charts, forecasts, and local harbour information before you go.