savvy navvy alternative
savvy navvy makes it feel effortless.
Effortless isn’t the same as verified.
savvy navvy did something hard: it made passage planning feel like car navigation, and a lot of people got out sailing because of it. The trouble starts under the keel. Independent reviewers have found its routes running through shallows and past hazards, on polars you aren’t allowed to change. OpenSail solves the same problem with every segment depth-checked and your boat’s own polar.
The short answer
Is OpenSail a good savvy navvy alternative?
For weather routing, yes. OpenSail verifies every segment of a returned route against GEBCO 15-arc-second bathymetry and your entered draft, accepts your own polar table by upload or hand-edit, and carries wave and ocean-current data, all in the $59/yr tier. On savvy navvy, offline charts and the departure scheduler begin at Explore (£95/yr) and ECMWF plus wave data are Elite only (£99/yr).
For charts, no. savvy navvy’s chart layer with Waterway Guides marina and anchorage detail is the best product on this comparison and OpenSail has no equivalent. Its tidal heights and tidal stream atlases for European waters are also ahead of ours.
The clean split: savvy navvy answers “where am I and what is there?” better than anyone. OpenSail answers “should I go, when, and by which line?” with the reasoning attached. Plenty of cruisers pay for both and use each for what it is good at.
- Routing tier
- OpenSail $59/yr · savvy navvy £59/yr
- Departure planning at
- OpenSail $59/yr · savvy navvy £95/yr
- Wave data at
- OpenSail $59/yr · savvy navvy £99/yr
- Editable polars
- OpenSail yes · savvy navvy reported fixed
Pick OpenSail if
You want the route argued for, your own boat’s numbers in the solver, and depth treated as a hard constraint rather than a warning layer.
Pick savvy navvy if
You want the best chart on your phone with marina and anchorage detail, European tidal streams, and an anchor alarm in the same app.
Competitor prices and features read from the vendors’ own pages on . Every source is linked at the foot of this page.
Under the keel
The part a beautiful chart can’t fix
Start with the thing that is uncomfortable to write about a competitor we otherwise admire.
We aren’t posting that to gloat. We’re posting it because it’s the exact failure mode OpenSail was built to close, and because a comparison page that only lists features is useless to somebody choosing a tool that will influence where their boat goes at night.
Two design decisions follow from it. First, depth is a hard constraint, not a warning layer. Every segment of a returned route is checked against GEBCO 15-arc-second bathymetry and the draft you entered, and where the depth data isn’t trustworthy the route says so on that segment instead of assuming deep water. Second, the returned geometry is checked against OpenStreetMap coastline polygons segment by segment, not waypoint by waypoint. A route that clips a headland between two legal waypoints is still a route that clips a headland.
Every segment of a returned route is checked against GEBCO 15-arc-second bathymetry and your entered draft. Not the waypoints. The line between them.
The founder’s family sailed for three years anchoring routinely within a kilometre of beaches. That’s where this stubbornness comes from. Offshore, a hundred metres of error is nothing. In the Exumas it is the difference between a good night and a very expensive one.
Your boat
A route for your boat, not a boat like yours
An isochrone solver is a polar table with a search algorithm wrapped round it. If the polar is wrong, everything downstream is confidently wrong: the arrival time, the departure recommendation, the whole plan.
Yachting World’s reviewer could not adjust savvy navvy’s polars. That means a heavy long-keeled cruiser with a full water tank, a folding prop and six months of growth gets routed as though she sails like the reference boat. She doesn’t. Every cruiser knows the boat is slower than the brochure; the software should know it too.
OpenSail takes the polar three ways, and shows you exactly what the solver will use:
- From the catalogue. Find her by name and get a starting curve you can then bend to reality.
- By file. Upload the polar your sailmaker, your instruments or your race programme produced.
- By hand. A grid you can type into, with a live polar diagram redrawing as you edit. Every cell the solver reads is in that grid, and nothing is dropped.
The full polars deep dive, including how the solver interpolates between wind speeds and what happens above your configured gust ceiling.
A weather map
A rhumb line and your judgement. Which is fine, until the judgement is being made at 0300 by someone who has been awake for nineteen hours.
OpenSail’s solver
Each ring is everywhere the boat could be after another three hours, given her polar, the forecast at that hour, the current, and the depth under her keel. The route is the cheapest path through nine of them. Figures from a real Tampa Bay → Nassau solve.
The money
What each tier actually withholds
savvy navvy’s tiering is where a lot of the frustration in the app-store reviews comes from, and it’s worth laying out plainly.
Essential (£59/yr) gives you charts, AIS to three miles, four-day trip planning and automated routing. It doesn’t give you offline charts. A navigation app that needs a signal is a navigation app that stops working at the moment it matters, and offline is the first thing most cruisers assume they already bought.
Explore (£95/yr) adds offline, tidal height graphs, plotter export and the departure scheduler. This is the tier most cruisers actually need.
Elite (£99/yr) is where the ECMWF model, wave data, the 14-day forecast and the anchor alarm live. Below Elite you’re planning passages against one atmospheric model with no sea state at all, which is a real limitation nobody mentions at signup.
OpenSail draws the line differently: waves, ocean currents, the departure planner and all four comfort modes ship in the $59 tier, and nothing the solver treats as a safety input sits above it. The extra forecast models and the disagreement layer at $149 are second opinions, not missing sea state.
- Windy Premium + plugin$21Routing via a community plugin, no chart data underneath
- OpenSail Voyager$59Unlimited routing, four comfort modes, departure planner
- LuckGrib + routing$90$29.99 app plus a $59.99 routing purchase, bought once
- savvy navvy Explore$121£95/yr — offline charts and the departure scheduler
- PredictWind Standard$249The first PredictWind tier listing weather routing
- PredictWind Professional$499Boat motion, high-res GRIBs, ocean currents, AI polars
Cheapest tier of each product whose own feature list includes weather routing, at list price, billed annually. savvy navvy converted from £95 at 1.27; they set US pricing separately. Windy’s figure buys Premium, not routing — the routing is a community plugin.
Line by line
OpenSail vs savvy navvy, capability by capability
| Capability | OpenSail | savvy navvy |
|---|---|---|
| Weather routing included at the entry paid tierWhether you can get an optimised route without buying the top of the price list. | ●$59/yr, unlimited | ●£59/yr |
| Free tier that solves a real routeWhether you can test the actual solver before paying, rather than only viewing forecasts. | ●1 route/week | ◐Limited planning |
| Per-segment depth verification against bathymetryWhether every leg of the returned route is checked against charted depth and your draft, rather than the grid being sampled at waypoints. | ●GEBCO 15″, per segment | ◐Hazard findings |
| Comfort as a first-class routing objectiveWhether you can ask for the passage your crew will tolerate instead of only the fastest one. | ●4 modes incl. Family | —Speed-optimised |
| Editable polars for your own boatWhether the route assumes your boat’s performance or a stand-in from a small library. | ●Editable + catalogue | —Not adjustable |
| Model disagreement measured along your routeWhether the app tells you where two independent models stop agreeing on your track, or leaves you to flip between tabs. | ●Verdict + band | —Single model below Elite |
| Says why it refused a routeWhether a failed solve explains the constraint that stopped it or returns nothing. | ●Structured refusals | —not offered |
| Plain-language briefing on which route and when to leaveWhether the app commits to a recommendation and shows its reasoning, or hands you a table. | ●Intelligence Layer | —Tables |
| Anchorage exposure scored hour by hourWhether you can check tonight’s anchorage for the sectors it is open to, in the same app that planned the passage. | ●In the map | ◐Alarm, not forecast |
| Alerts you when a new model run worsens a planned routeWhether you stop re-checking the forecast manually once a passage is planned. | ●Threshold-gated | —not offered |
| Runs in a browser with no installWhether crew, delivery skippers and shore support can open your plan on whatever machine is in front of them. | ●PWA, installs optional | ◐App-first |
| Documented public APIWhether you can pull routes into your own dashboard, race committee tooling or boat systems. | ●REST, keyed | —not offered |
| Pause the subscription for haul-outWhether you pay for the months your boat is on the hard. | ●Built in | —not offered |
● included◐ partial or workaround＄ costs extra— not offered
The other side
Where savvy navvy wins
Where savvy navvy is the better buy
Written by us, about them. If one of these describes your boat, buy theirs — you will be happier and we would rather you came back later than churned in a month.
- The chart layer is the best on this page, full stop. Savvy Charts render cleanly, the marina and anchorage data from Waterway Guides earns its place on passage, and OpenSail doesn’t have an equivalent.
- Onboarding is superb. A first-time skipper can plan a coastal hop in ninety seconds without reading anything, and that’s much harder to build than it looks.
- Tidal heights and tidal stream atlases for European waters are properly done, and European coastal sailors lean on them daily.
- Anchor alarm, AIS overlay and NMEA instrument connection make it a plausible single app at the chart table.
If you sail the Solent, the Baltic or the Balearics and your planning problem is tidal gates rather than weather windows, savvy navvy is the better tool this season and probably next. Our tidal work is real but it isn’t shipped, and we aren’t going to claim a roadmap item as a feature to win a comparison.
Questions sailors actually ask
What is the best savvy navvy alternative for passage planning?
It depends on what you use savvy navvy for. If you use it mainly as a chart with marina and anchorage information, nothing on this page replaces it and you should keep it. If you use it to decide when and how to make a passage, OpenSail is the stronger tool: your own editable polar, depth checked on every segment of the returned route, and a briefing that explains which route it picked.
A lot of European cruisers end up running both. savvy navvy on the phone at the chart table, OpenSail on a laptop the night before.
Is savvy navvy’s routing accurate?
Independent reviewers have raised specific concerns. Yachting World’s tested review reported routes taking the boat into dangerous shallows and passing within metres of hazards and lee shores in strong winds, and noted the performance polars can’t be adjusted to your boat. Practical Sailor found the route and timing modelling didn’t hold up against a real passage. Both reviews are linked below; read them rather than taking our summary for it.
Which is cheaper, OpenSail or savvy navvy?
OpenSail. Unlimited routing, all four comfort modes, the departure planner, and wave and ocean-current data cost $59/yr; every forecast model and the model-disagreement layer come with Passage at $149/yr. On savvy navvy, offline charts and the departure scheduler start at Explore (£95/yr), and ECMWF plus wave data are Elite only (£99/yr). savvy navvy sets US pricing separately from its sterling list, so check their US page for your own currency.
Does OpenSail have charts like savvy navvy?
Not like theirs, no. OpenSail carries NOAA electronic navigational charts for US waters as a map overlay, OpenStreetMap coastlines, and GEBCO bathymetry that the solver enforces. What it doesn’t have is savvy navvy’s worldwide chart product with integrated marina and anchorage detail, and we aren’t going to catch up on that soon. OpenSail is a routing and weather tool that knows where the water is; savvy navvy is a chart that also routes.
Can I put my own boat’s polar into OpenSail?
Yes, three ways. Pick her from the catalogue, upload a polar file, or type the table in by hand in a grid that shows a live diagram as you edit. Every cell of the polar the solver actually uses is visible and editable, which matters because a routing engine is only as honest as the boat model underneath it. If your boat is slower than her design numbers with a full cruising load and a dirty bottom, you can say so.
Does OpenSail do tides?
Not yet at savvy navvy’s level, and this is the honest gap. Copernicus Marine ocean currents feed the solver directly, so a Gulf Stream or a Med surface set is already in your route. Tidal heights and the tidal stream atlases European coastal sailors rely on are in build, not shipped. If you’re threading the Alderney Race next week, savvy navvy is the tool for that job and we would say so at the bar.
Where these numbers come from
Every competitor price and feature on this page was read from the vendor’s own page or a named independent test. Last checked . Prices change; if you find one of these out of date, tell us and we will fix it.
- savvy navvy — PricingEssential, Explore and Elite prices, and the feature each tier withholds.
- Yachting World — best navigation apps testedIndependent test findings on routing near hazards and fixed polars.
- Practical Sailor — Navigation App Review: savvy navvyIndependent review of route and timing accuracy against real passages.
PredictWind, savvy navvy, Windy.com and LuckGrib are trademarks of their respective owners. OpenSail is not affiliated with, endorsed by, or sponsored by any of them. Comparisons describe publicly documented capability at the date above.
Compare something else
Run your usual passage through both
Enter your boat’s real polar, solve the hop you make most often, and look at the minimum depth each route holds. That comparison takes about ten minutes and it’s the only one that matters.
Plan a passage — freeFree account, no card. If it doesn’t beat what you use now, close the tab. We won’t email you about it.