Comparison

Bunker One vs Saybolt Viscosity

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

Head to head
About

Bunker One

This app provides a suite of calculators for marine fuel standards, including CCAI, Cetan Index, and blending calculations. It supports ISO 8217 and ASTM standards, with all inputs and outputs in SI units. Users can also access news and updates from the developer.

Highlights
  • ISO 8217 fuel standard lookup
  • CCAI Number calculation
  • Cetan Index calculation (old & new methods)
  • Fuel blending calculators (viscosity, sulphur)
  • Injection temperature calculation
  • Energy and price relation calculations
  • News updates from developer
Features
Read full description

This application by Bunker One, is a small practicable tool for look up the ISO 8217 - 2005, 2010/2012, 2017 & 2024 standards for residual- and distillate marine fuels. Programmed calculators are included for different fuel related calculations. Calculators programmed as below.: -CCAI Number according ISO 8217 -Cetan Index ASTM - D 976 - 80 (old method) ASTM - D 4737 - 87 (new method) -Deviation calculations according Bunker One -Energy and price relations according Bunker One -Fuel Blending - Viscosity blending according ASTM - D 7152 Sulphur blending according Bunker One -Injection temperature according Bunker One -Reproducibility -Specific Energy gross and net content according ISO 8217 -Viscosity Index according ASTM - D 341 -Volume Correction Factor according ASTM D1250-80 Table 5B General for all calculators is that all entries shall be in SI units. And results also given in SI units. Where there is a differentiation between Distillates and Residual fuels, distillates are defined with density lower than 900 kg/m3 Where there is a differentiation between Straight Run fuel and Cracked fuels, straight run fuels are defined with density lower than 950 kg/m3 News published on our web page Bunkerone.com will be pushed to the app holders and publish with link to the web under the "news" bar

About

Saybolt Viscosity

This application serves as a calculator for converting viscosity and temperature values for petroleum fuels. It allows users to convert Kinematic Viscosity in Centistokes to desired target values across different temperature scales. In landscape mode, it transforms into a slider for visual comparison of viscosity units.

Highlights
  • Viscosity/Temperature conversion calculator
  • Converts Kinematic Viscosity (cSt)
  • Supports Fahrenheit and Celsius
  • Landscape slider for unit comparison
  • Compares Centistokes to Saybolt Universal Seconds and Furol
Read full description

Welcome to the Viscosity/Temperature conversion app developed by Saybolt. This App is a handy Viscosity/Temperature conversion calculator for petroleum fuels. The calculator converts the Kinematic Viscosity in Centistokes (cSt) at a reference Temperature in Fahrenheit or Celcius to the desired target value. The App changes into a traditional Viscosity/Temperature slider when the mobile device is held in landscape position. By reading the slider scale under the hairline Kinematic Viscosity units can be compared, such as the Saybolt Universal Seconds or Saybolt Seconds Furol, with the nowadays more widely used Centistokes. Temperature and viscosity conversions with the slider are indicative.

Screenshots

Bunker One4 screens
Saybolt Viscosity3 screens

Verdict

The call

The clearest difference is rating: Bunker One at 4.5 against Saybolt Viscosity's 3.0. Bunker One also leads on update cadence (every 3 months vs every 14 months). Saybolt Viscosity's advantage is iOS requirement (9.3 vs 15.6). On price, ratings volume, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Bunker One holds the better App Store score, 4.5 against 3.0. Both are backed by a comparable volume of ratings — 2 and 2 respectively.

UpkeepUpdate frequency

Bunker One ships an update every 3 months, Saybolt Viscosity every 14 months. Both last shipped on October 23, 2026.

Scorecard3 real differences · 7 level
Bunker One versus Saybolt Viscosity: the parameters behind the verdict, then further details
ParameterBunker OneSaybolt Viscosity
PriceFreeFree
Rating4.5 (2 ratings) — better3.0 (2 ratings)
Positive reviews0.0% of reviews—
Number of ratings22
Update frequencyEvery 3 months — betterEvery 14 months
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS15.69.3 — better
Further details — not scored
Size16 MB3 MB
Age rating4+4+
DeveloperAskappsSaybolt International B.V.

Customer experience

Bunker One

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

Saybolt Viscosity

All ratings2 ratings
Positive50.0%
Neutral0.0%
Negative50.0%

In-app purchases

None

Bunker One

No in-app purchases

None

Saybolt Viscosity

No in-app purchases

Questions

Is Bunker One free?
Bunker One is free to download, with no in-app purchases.
Is Saybolt Viscosity free?
Saybolt Viscosity is free to download, with no in-app purchases.
Which has better reviews, Bunker One or Saybolt Viscosity?
Bunker One is rated higher. Bunker One averages 4.5 out of 5 from 2 ratings, while Saybolt Viscosity averages 3.0 from 2 ratings.
Do Bunker One or Saybolt Viscosity have ads?
Neither Bunker One nor Saybolt Viscosity shows ads.
Which is updated more often, Bunker One or Saybolt Viscosity?
Bunker One ships an update every 3 months, and Saybolt Viscosity every 14 months. Most recently, Bunker One was updated on October 23, 2026 and Saybolt Viscosity on October 23, 2026.

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