Comparison

Nautical Calculator. vs Maritime Master

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Nautical Calculator.

Features
Read full description

Nautical Calculator is a complete toolkit designed for sailors, marine engineers, boating enthusiasts, and navigation professionals. Perform essential nautical calculations quickly and accurately with an easy, user-friendly interface. Whether you're at sea, studying navigation, or working in the marine industry, this app helps you compute distances, bearings, speed, fuel, tides, ETA, and many other important nautical parameters. Save your time, improve accuracy, and keep all your marine tools in one place. Key Features: Course, distance & bearing calculations, Speed, fuel, and consumption estimations, Time & ETA calculations, Sail-related and marine engineering formulas, Unit conversions for knots, nautical miles & more,, Clean, intuitive, seafarer-friendly interface, Save and share results instantly, Useful for sailors, captains, students & maritime workers, A reliable companion for boating, yachting, navigation training, and professional maritime use. in-app purchase included Lifetime to Remove Ads Privacy Policy : https://docs.google.com/document/d/1Dn1gNdDP2AHL7sg-px4rxdLAcoGHlNB8/edit#heading=h.1ionsc3v3xmq Terms and Condition : https://docs.google.com/document/d/1t-LREPKByKaM0UkbIo4o0E1gdAYs21Oe30EfGxenEss/edit?usp=sharing

About

Maritime Master

This app provides a comprehensive suite of 88 professional maritime calculators for navigation, celestial observation, tides, stability, weather, engineering, and more. It's designed for maritime professionals and enthusiasts, offering offline functionality and citing all formulas with their official sources.

Highlights
  • 88 professional maritime calculators
  • Offline functionality
  • Navigation calculations
  • Celestial observation tools
  • Stability and cargo calculations
  • Unit converters
Features
Read full description

CalcDeck is the complete calculation toolkit for life at sea. It brings 88 professional maritime calculators into one beautifully designed iOS app, covering navigation, celestial observation, tides, stability and cargo, weather, engineering, safety, commercial voyage work, yacht and small craft performance, regulatory compliance and unit conversion. Whether you are a Master Mariner, deck officer, marine engineer, maritime cadet, yacht skipper or weekend sailor, CalcDeck replaces a shelf of reference books, a scratch pad and a pocket full of single-purpose apps. Every formula is cited with its textbook or IMO source, so you can verify the working and trust the result. CalcDeck is built by Maritime Master, the team behind COLREG Master, Nav Lights and IALA Buoyage, and is engineered to the same professional standard trusted by cadets and officers worldwide. What is inside Navigation (12 calculators): great-circle and rhumb-line distance, course to steer, ETA, set and drift, three-point fix, running fix, dead reckoning, cross-track error, waypoint bearing, speed-time-distance, departure and DMP, Mercator sailing. Celestial (8 calculators): sight reduction, meridian passage, altitude corrections, sunrise, sunset and twilight times, Polaris latitude, compass error by amplitude, azimuth of the sun, and chronometer error. Tidal (6 calculators): tidal height by the rule of twelfths, secondary port corrections, tidal streams, height at a given time, time at a given height, and clearance under bridges. Stability and Cargo (9 calculators): GM and list, trim and draft survey, free surface correction, deadweight and displacement, cargo load, block coefficient, TPC and MCTC, and final draft after loading. Weather (6 calculators): true wind, apparent wind, relative humidity, dew point, Beaufort scale conversion, and barometric trend. Engineering (10 calculators): fuel consumption and ROB, daily fuel burn, propeller slip, shaft power, specific fuel consumption, bunker density correction, trim tank transfer, admiralty coefficient, engine load, and voyage fuel planning. Safety (5 calculators): distance off by vertical sextant angle, horizon distance, dipping range, turning circle, and stopping distance. Yacht and Small Craft (5 calculators): hull speed, sail area to displacement, displacement to length, capsize screening, and ballast ratio. Commercial and Voyage (6 calculators): voyage cost, laytime, demurrage, freight rate per tonne, charter economics, and port disbursements. Regulations and Compliance (6 calculators): MARPOL discharge limits, SOLAS LSA requirements, STCW rest-hour compliance, load line zones, ballast water exchange, and garbage record categorisation. Unit Converters (12 calculators, all free): distance, speed, temperature, pressure, volume, mass, area, power, energy, angle, time and fuel. Every unit a mariner needs. Why CalcDeck CalcDeck works fully offline, so there is no signal, no signup and no interruption when you need an answer at sea. It is a native SwiftUI app designed for iPhone and iPad on iOS 17 and later, with a clean navy and gold Maritime Master design, dark mode support, favourites, and a Calc Pad that lets you pin your most-used tools for instant access on watch. There are no advertisements, no tracking and no subscriptions. Free and Pro You can try CalcDeck at no cost. All 12 unit converters and a selection of essential calculators in every professional category are included free. Unlock the full 85-calculator suite with a single one-time in-app purchase that is yours forever across all your devices. Who it is for CalcDeck is used by deck officers and Masters on coastal and ocean passages, by marine engineers calculating fuel, power and performance, by maritime cadets preparing for OOW, Chief Mate and Master examinations, by yacht skippers and RYA students, by cruising sailors, by pilots, harbourmasters and port operations staff, and by naval architects, surveyors and marine consultants.

Screenshots

Nautical Calculator.4 screens
Maritime Master4 screens

Verdict

The call

The clearest difference is update cadence: Maritime Master at daily against Nautical Calculator.'s every 5 months. Nautical Calculator.'s advantage is iOS requirement (15.6 vs 17.6). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Nautical Calculator. sells 1 one-off in-app purchase and Maritime Master sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Nautical Calculator. ships an update every 5 months, Maritime Master daily. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 8 level
Nautical Calculator. versus Maritime Master: the parameters behind the verdict, then further details
ParameterNautical Calculator.Maritime Master
PriceFreeFree
Rating—3.0 (1 ratings) — better
Positive reviews—0.0% of reviews
Number of ratings—1 — better
Update frequencyEvery 5 monthsDaily — better
AdsNoNo
In-app purchasesYesYes
Monetization—Free
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better17.6
Further details — not scored
Size43 MB7 MB
Age rating4+9+
DeveloperNanjibhai GorasiyaMARITIME MASTER LIMITED

In-app purchases

1 purchases

Nautical Calculator.

One-time1
  • Lifetime premium$12.99
1 purchases

Maritime Master

One-time1
  • CalcDeck Pro$14.99

Questions

Is Nautical Calculator. free?
Nautical Calculator. is free to download, with in-app purchases available.
Is Maritime Master free?
Maritime Master is free to download, with in-app purchases available.
Do Nautical Calculator. or Maritime Master have ads?
Neither Nautical Calculator. nor Maritime Master shows ads.
Which is updated more often, Nautical Calculator. or Maritime Master?
Nautical Calculator. ships an update every 5 months, and Maritime Master daily. Most recently, Nautical Calculator. was updated on October 30, 2026 and Maritime Master on October 31, 2026.

Other comparisons