PredictWind alternative
PredictWind will route you.
It won’t tell you why.
PredictWind is the boat that most of us learned on, and it earned that. But routing starts at $249 a year, the answer arrives as a track on a chart with no reasoning attached, and when the solver can’t find a route it simply doesn’t find one. OpenSail routes from $59, shows its working, and says out loud what stopped it.
The short answer
Is there a serious PredictWind alternative in 2026?
Yes. OpenSail is the closest like-for-like alternative for cruising sailors: unlimited weather routing at $59/yr against PredictWind’s $249/yr Standard tier, with four comfort modes, a departure planner, and per-segment depth verification against GEBCO bathymetry included at that price. PredictWind’s own pricing page lists Weather Routing under Standard; the $29 Basic tier is forecasts and imagery.
What OpenSail adds is explanation. It reports why a route was refused, clustered by cause and pinned to a position. It solves your passage in four comfort modes and recommends one in plain language. It re-samples GFS and ECMWF along your solved track and tells you where they stop agreeing. PredictWind gives you more forecast; OpenSail gives you more argument.
PredictWind stays the better buy for two specific sailors: anyone who depends on its proprietary PWG and PWE models at 1 km and 8 km, and anyone running a DataHub on an Iridium mid-ocean. Neither has an OpenSail equivalent, and we aren’t going to pretend otherwise.
- Routing starts at
- OpenSail $59/yr · PredictWind $249/yr
- Free tier routing
- OpenSail solves 1 route/week · PredictWind none
- Top tier
- OpenSail $249/yr · PredictWind $499/yr
- Five-year cost
- $295 vs $1,245 for the routing tier
Pick OpenSail if
You cruise, you want the route explained rather than asserted, and you would rather not spend $249 before the solver will talk to you.
Pick PredictWind if
You depend on PWG or PWE in a region where they’re demonstrably sharper, or your offshore weather comes through a DataHub on an Iridium.
Competitor prices and features read from the vendors’ own pages on . Every source is linked at the foot of this page.
The money
The $249 gate
Here’s the thing that bothers us about the category. Weather routing isn’t a luxury feature. It’s the feature. It’s the reason a sailor opens a weather app instead of looking out of the companionway. And on PredictWind it sits behind the third tier of four.
You can pay $29 and get lightning, radar, satellite imagery and 1 km wind maps, all of it good. What you can’t do is ask the software where to sail. For that the price is $249. Add boat motion, high-resolution routing and ocean-current GRIBs and you’re at $499.
OpenSail took the opposite decision. The solver is the product, so the free account solves a real passage. Not a preview, not a watermarked track: a full isochrone solve with your draft and your polar, capped at one a week and 200 nm. Unlimited routing at any distance, all four comfort modes and the departure planner cost $59 a year, which is less than a night in most marinas.
- 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.
We aren’t claiming to be the cheapest thing on this chart, and you can see that we’re not. LuckGrib is bought once, and from about month nineteen its routing kit beats our Voyager tier on pure cost. If price is the only axis you care about, go and read that page instead. It’s on our own site because a comparison you can’t lose is a comparison nobody believes.
The engine
What the solver is actually checking
Both products run isochrone routing, so the argument isn’t whether there’s a solver. It is what each one quietly skips on the way to a pretty line.
OpenSail expands time-layered reachability fans in native Rust, then checks the returned geometry twice: every segment against GEBCO 15-arc-second bathymetry and your entered draft, and every segment against OpenStreetMap coastline polygons. Every yard between two waypoints gets the same scrutiny as the waypoints themselves, and within a mile of shore that is where sailors actually get into trouble.
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.
Half a million candidate states get expanded and thrown away on a typical Gulf Stream crossing. The ones that survive did so because there was water under them the whole way.
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.
Our founder’s family spent three years anchoring within a kilometre of beaches in the Bahamas and the eastern Caribbean. That isn’t a marketing anecdote, it’s the reason depth is a hard constraint in this solver instead of a warning layer you can turn off. Where the bathymetry isn’t trustworthy, the route says so per segment rather than quietly assuming zero depth is deep water.
The difference
A route you can argue with is a route you can trust
Ask PredictWind for a route and you get a route. Ask it for a route it can’t compute and you get nothing much. Neither behaviour is wrong exactly, but both leave the sailor doing the interpretation at the least convenient moment.
OpenSail was built the other way round. Every solve produces a decision and the reasoning behind it, and every failed solve produces a diagnosis.
The solver expanded 318,004 candidate states and rejected every one that reached Great Harbour. Here’s what stopped them.
- Depth under keel below draft + safety margin61%
- Segment crosses charted land22%
- Gust above the vessel’s configured ceiling14%
- Other3%
Densest rejection cluster near 26.6°N, 78.9°W — the bank north of the cut. Try a draft under 1.5 m, a later departure, or the northern approach.
No other product on this page documents anything like this. A refusal you can act on is worth more than a route you can’t interrogate. Worked example: the panel is the real product surface, the numbers illustrate a typical shallow-bank refusal.
That panel is the one people mention first. Ask for Bimini with a two-metre draft on a spring low and most tools spin, then shrug. This one tells you that 61% of the rejected candidates died on depth, shows you the cluster on the bank north of the cut, and suggests the northern approach. You can act on that. A spinner you can’t.
Where two models stop agreeing on your track
The other half of honesty is uncertainty. Every serious sailor already does this by hand, flipping between GFS and ECMWF in two tabs and squinting at the difference. OpenSail re-samples both models at your route’s own positions and times, through a single interpolator, and renders the divergence on your track with a verdict attached.
Both models re-sampled at your route’s own positions and times, through one interpolator, so the difference you see is the models disagreeing rather than two apps rounding differently. Illustrative trace from a Gulf Stream crossing.
Agreement holding to +30h and then opening 14 knots is a very different passage from agreement holding all the way to landfall, and it should change what you do on Thursday morning. PredictWind will happily show you both models. It won’t tell you that this is the hour they part company on your route.
Line by line
OpenSail vs PredictWind, capability by capability
| Capability | OpenSail | PredictWind |
|---|---|---|
| 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 | ＄$249/yr tier |
| Free tier that solves a real routeWhether you can test the actual solver before paying, rather than only viewing forecasts. | ●1 route/week | —Forecasts only |
| 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 | ◐Not documented |
| 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 | ＄Boat motion at $499 |
| Editable polars for your own boatWhether the route assumes your boat’s performance or a stand-in from a small library. | ●Editable + catalogue | ＄AI polars at $499 |
| 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 | ◐Overlay by eye |
| 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 + overlays |
| 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 | ◐Separate app |
| 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 | ◐Web + native apps |
| 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 PredictWind wins
Where PredictWind 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.
- PWG and PWE are their own models, run in-house at 1 km and 8 km. Nobody else on this page has proprietary forecast models, and in a few regions they are demonstrably sharper than the global runs.
- The satellite story is finished hardware, not a workflow. DataHub is a physical box that sits on your Iridium and just works, and there’s no substitute for that on a boat 900 miles out.
- Boat-motion outputs — roll, vertical acceleration, slamming incidence — are rare, and if you’re moving a heavy displacement boat with a nervous crew, they earn their keep.
- Twenty years of accumulated regional forecasting knowledge, and a support organisation that exists.
One more thing worth saying, because it isn’t on any feature list. PredictWind has been doing this for two decades and has a support organisation, an accounts department and a phone number. OpenSail has a small team and an inbox. We answer fast, but we aren’t pretending to be the same kind of company yet.
Practical
Trying both takes ten minutes
There’s no import, no export and no migration, because OpenSail runs in a browser and keeps nothing you would need to move. The honest test is this one:
- Make a free account and enter your boat. Pick her from the catalogue or paste your own polar table; both take about a minute.
- Solve the passage you already solved in PredictWind this morning. Same departure, same destination.
- Put the two tracks side by side. Look at where they differ and, more usefully, at whether either one goes somewhere you wouldn’t have gone.
- Then run Compare All Modes and read the briefing. That’s the part that has no PredictWind equivalent, and it’s the part people either love immediately or find unnecessary. Both reactions are fine.
Keep both subscriptions if the boat can afford it. A second independent opinion on a forecast has never hurt anybody, and we would rather earn a place in your rotation than demand the whole thing.
Questions sailors actually ask
What is the best PredictWind alternative in 2026?
For most cruising sailors it’s OpenSail, on price and on explanation. PredictWind’s own pricing page lists Weather Routing under the $249/yr Standard tier; OpenSail routes without limits from $59/yr and solves one real route a week on the free account. If you need proprietary 1 km models or a DataHub bolted to an Iridium, stay with PredictWind, because nobody else has those.
If you want a one-time purchase instead of any subscription, LuckGrib is the honest answer and it costs $89.98 once.
Is OpenSail cheaper than PredictWind?
Yes, at every tier that does the same job. Unlimited routing with all four comfort modes and the departure planner is $59/yr on OpenSail. The cheapest PredictWind tier whose feature list includes Weather Routing is Standard at $249/yr. Their Professional tier, which adds boat motion and high-resolution GRIBs, is $499/yr; OpenSail’s top tier is $249/yr and includes API keys. Over five years that’s $295 against $1,245.
Does OpenSail have PredictWind’s PWG and PWE models?
No, and it never will. Those are PredictWind’s own runs and they’re a real advantage in the regions where they’re tuned. OpenSail serves GFS, ECMWF IFS, HRRR at 3 km on the US coast, AROME at 2.5 km for the Channel, Biscay and the western Med, plus Copernicus Marine currents and waves. What we do with those models is different: they get re-sampled along your actual solved track so you can see where two of them stop agreeing, instead of being overlaid for you to eyeball.
Can I use OpenSail offshore over a satellite connection?
Partly, and we would rather say so plainly than oversell it. OpenSail cuts GRIB files to your route corridor and your airtime budget rather than shipping you an ocean basin, and the map caches the last real forecast with a banner that says how old it is. PredictWind’s offshore story is more finished than ours: the DataHub is physical hardware that sits on the Iridium and works without a browser. If you’re three weeks into a Pacific crossing, buy theirs.
What does OpenSail do that PredictWind doesn’t do at all?
Four things, and they’re the reason the product exists. It tells you why a route was refused, clustered by cause and located on the chart, instead of returning nothing. It treats comfort as an objective, so Family mode will trade two hours for half the heel. It measures model disagreement along your own track and gives you a verdict. And it writes the decision in plain language: which of four solved routes to take, when to leave, and what the runner-up would have cost you.
Smaller, but people notice: you can pause your subscription while the boat is hauled out, and there’s a documented REST API.
Is it hard to switch from PredictWind?
There is nothing to migrate. OpenSail runs in a browser, so make a free account, enter your boat once, and solve the same passage you solved this morning in PredictWind. Compare the two tracks. If ours isn’t better for your boat, you have lost ten minutes and no money. Keep both for a season if you like; plenty of people do, and we would rather be the second opinion you trust than the subscription you resent.
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.
- PredictWind — Features, Packages and PricingTier names, annual prices, and which tier first lists Weather Routing.
- PredictWind Help Centre — Standard vs ProfessionalBoat-motion modelling, high-resolution GRIBs and ocean currents sitting above Standard.
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
Solve the same passage twice and compare
Free account, your boat, a real isochrone solve. If PredictWind’s track is better for your boat, you will know inside ten minutes.
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.