Comparison

MultiDeco vs Buoyancy Calc

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

Head to head
About

MultiDeco

This app calculates dive decompression for technical scuba divers using VPM and ZHL-16 models. It supports various gas mixes, planning methods for open circuit and rebreathers, and includes tools for gas blending and depth calculations.

Highlights
  • VPM and ZHL-16 decompression models
  • Support for nitrox and trimix
  • OC and CCR planning
  • Bailout planning
  • Gas blending utility
  • Depth calculation tools
Read full description

A dive decompression calculator for technical scuba divers. MultiDeco presents the VPM and ZHL-16 decompression model and includes VPM-B, VPM-B/E, ZHL model versions and ZHL-16 + GF. The diver can specify any combination of nitrox or trimix, and as many deco gases as required. Planning methods include both OC and Closed Circuit Rebreather. It includes planning for bailouts with SCR and OC legs in a CCR plan. Includes details of ppO2, END, and gas consumptions. This program includes many of the features from the desktop version such as conservatism adjustments, extended stops, adjustable last stops, the planning monitor system and extensive control over many other planning features. Also included is a set of dive planning tools for calculating best mix, maximum operating depth (MOD), END, EAD and other planning considerations. The Mixer utility for blending nitrox and trimix, is included too.

About

Buoyancy Calc

Calculate the optimal weight for scuba diving based on environmental factors. Input your weight, water type, tank, and exposure suit to get a suggested weight for neutral buoyancy.

Highlights
  • Calculate suggested diving weight
  • Adjust for water type
  • Adjust for tank type
  • Adjust for exposure suit
  • Supports pounds and kilograms
Features
Read full description

Quickly find out the suggested weight you should add when scuba diving in different environments. Based on PADI's Peak Performance Buoyancy basic weighting guideline*. Enter your weight in pounds or kilograms, and additionally set the type of water, tank, and exposure suit to dial in a suggested amount of weight to help keep you neutrally buoyant. *Note that this app and the developer are not officially a representative of PADI. This app will give the user a good estimate of the weight needed for the environment selected, but there are always adjustments needed to achieve peak performance, based on gender, physique, exposure suit age, accessories, etc.

Screenshots

MultiDeco4 screens
Buoyancy Calc1 screens

Verdict

The call

The clearest difference is price: Buoyancy Calc at Free against MultiDeco's $48.99. Buoyancy Calc also leads on iOS requirement (15.6 vs 17.6). MultiDeco's advantage is rating (3.9 vs 3.1). On review sentiment, ratings volume, update cadence and ads 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

Buoyancy Calc is free to download; MultiDeco costs $48.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

MultiDeco holds the better App Store score, 3.9 against 3.1. Both are backed by a comparable volume of ratings — 11 and 25 respectively. Written reviews complicate that: 39% of MultiDeco's written reviews are positive against 40% of Buoyancy Calc's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on September 19, 2026 and June 8, 2026 respectively.

Scorecard4 real differences · 6 level
MultiDeco versus Buoyancy Calc: the parameters behind the verdict, then further details
ParameterMultiDecoBuoyancy Calc
Price$48.99Free — better
Rating3.9 (11 ratings) — better3.1 (25 ratings)
Positive reviews38.9% of reviews40.0% of reviews — better
Number of ratings1125 — better
Update frequencyEvery 3 monthsEvery 3 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.615.6 — better
Further details — not scored
Size2 MB1 MB
Age rating4+4+
DeveloperHHS Software Corp.Eric Hamiter

Customer experience

MultiDeco

All ratings11 ratings
Positive63.6%
Neutral18.2%
Negative18.2%
Written reviews18 reviews
Positive38.9%
Neutral22.2%
Negative38.9%

Buoyancy Calc

All ratings25 ratings
Positive44.0%
Neutral12.0%
Negative44.0%
Written reviews25 reviews
Positive40.0%
Neutral12.0%
Negative48.0%

In-app purchases

None

MultiDeco

No in-app purchases

None

Buoyancy Calc

No in-app purchases

Questions

Is MultiDeco free?
MultiDeco costs $48.99, with no in-app purchases.
Is Buoyancy Calc free?
Buoyancy Calc is free to download, with no in-app purchases.
Which has better reviews, MultiDeco or Buoyancy Calc?
MultiDeco is rated higher. MultiDeco averages 3.9 out of 5 from 11 ratings, while Buoyancy Calc averages 3.1 from 25 ratings.
Do MultiDeco or Buoyancy Calc have ads?
Neither MultiDeco nor Buoyancy Calc shows ads.
Which is updated more often, MultiDeco or Buoyancy Calc?
MultiDeco ships an update every 3 months, and Buoyancy Calc every 3 months. Most recently, MultiDeco was updated on September 19, 2026 and Buoyancy Calc on June 8, 2026.

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