Comparison

Stoichiometry Pro vs DrPhos' Stoichiometry

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

Head to head
About

Stoichiometry Pro

Features
Read full description

Stoichiometry Pro targets common stoichiometric tasks: balancing chemical reactions of unlimited number of components, finding molar masses, moles and masses of reactants and products and defining the limiting reagent, based on chemical formulas, stoichiometric coefficients, and any quantitative data provided. The app analyses chemical reaction typed in “Reaction” field, balances it (if possible), finds molar masses and builds table with list of compounds (reagents and products coloured differently), for quantitative data input. All that triggered by pressing the = button. Example 1: How many moles of H3PO4 are needed in order to obtain 2.0 g of NH4NO3, in the reaction: H3PO4 + (NH4)2MoO4 + HNO3 = (NH4)3PO4(MoO3)12 + NH4NO3 + H2O Solution: The first step is balancing chemical reaction and finding molar masses, since moles-mass conversion is needed. Reaction is balanced and all molar masses are calculated automatically by pressing the “=” button. H3PO4 + 12(NH4)2MoO4 + 21HNO3 = (NH4)3PO4(MoO3)12 +21NH4NO3 + 12H2O, The next step is to find the moles of NH4NO3 from the mass (2.0 g), and then convert them to moles of H3PO4 based on 1:21 ratio obtained from the balanced reaction. Stoichiometry application provides data table that comprised of masses and mole rows for data available before reaction initiated and obtained or left after the reaction is accomplished. When calculate button that pointing towards products, ▶▶ is pressed, the final masses and moles are calculated from the initially provided amounts of reactant and products. On the opposite, when the calculate button pointing left,◀◀, is pressed, then initial reactant and product amounts that would be required to achieve the provided final state are calculated. The later is exactly matches our situation, as we need to find the initial amount of H3PO4 from the final, known NH4NO3 mass. So we set the NH4NO3 mass (2.0 g) to the final mass field and press calculate button ◀◀ to automatically fill the table with all masses and moles for all components. Apparently, 1.19 mmoles of H3PO4 are required to get 2.0 g of NH4NO3. Important Points: Either moles or masses can be filled in, but if both are provided and they don’t match, then the moles value will have a preference. For balancing redox reactions please refer to Electrochemistry application.

About

DrPhos' Stoichiometry

This tool simplifies solving chemical reaction problems by allowing users to input balanced equations and identify known and unknown compounds. It instantly calculates moles and mass, assisting students with various stoichiometry challenges.

Highlights
  • Mole, mass, and volume conversions
  • Balanced chemical equation support
  • Compound selection
  • Limiting reactant detection
  • High school and college chemistry focus
Features
Read full description

Solve Stoichiometry Problems Fast The DrPhos Stoichiometry Tool makes solving chemical reaction problems simple. Enter a balanced equation, choose known and unknown compounds, and instantly calculate moles and mass. Designed for chemistry students, this tool walks you through the stoichiometric process with clean visuals and intelligent logic. Whether you’re solving basic mole ratios or limiting reactant problems, this app keeps your work fast, accurate, and focused. Features: • Supports mole, mass, and volume conversions • Works with balanced chemical equations • Select known and unknown compounds easily • Built-in limiting reactant detection • Ideal for high school and college chemistry Use this app on its own or unlock it within the full DrPhos GenChem Helper suite to streamline your chemistry toolkit.

Screenshots

Stoichiometry Pro4 screens
DrPhos' Stoichiometry4 screens

Verdict

The call

The clearest difference is in-app purchases: Stoichiometry Pro at none against DrPhos' Stoichiometry's 11. DrPhos' Stoichiometry's advantage is update cadence (every 3 weeks vs every 4 months) and price ($0.99 vs $3.99). On ads, device support and iOS requirement 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

Stoichiometry Pro costs $3.99 and DrPhos' Stoichiometry $0.99 up front. DrPhos' Stoichiometry sells 11 one-off in-app purchases. Stoichiometry Pro asks for nothing beyond the download.

UpkeepUpdate frequency

Stoichiometry Pro ships an update every 4 months, DrPhos' Stoichiometry every 3 weeks. The most recent releases landed on August 20, 2026 and September 20, 2026 respectively.

Scorecard3 real differences · 6 level
Stoichiometry Pro versus DrPhos' Stoichiometry: the parameters behind the verdict, then further details
ParameterStoichiometry ProDrPhos' Stoichiometry
Price$3.99$0.99 — better
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyEvery 4 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Paid
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.0 — better17.2
Further details — not scored
Size2 MB15 MB
Age rating4+4+
DeveloperRoman VolinskyMonte L Helm

In-app purchases

None

Stoichiometry Pro

No in-app purchases

11 purchases

DrPhos' Stoichiometry

One-time11
  • Significant Figures Counter$0.99
  • Science Calculator$0.99
  • Quadratic Equation Solver$0.99
Show 8 more
  • Kinetics$0.99
  • Molar Mass Calculator$0.99
  • General Chemistry Naming$0.99
  • Ionic Compound Builder$0.99
  • Solution Concentrations$0.99
  • Reaction Balancer$0.99
  • pH Calculator$0.99
  • Stoichiometry$0.99

Questions

Is Stoichiometry Pro free?
Stoichiometry Pro costs $3.99, with no in-app purchases.
Is DrPhos' Stoichiometry free?
DrPhos' Stoichiometry costs $0.99, and also offers in-app purchases.
Do Stoichiometry Pro or DrPhos' Stoichiometry have ads?
Neither Stoichiometry Pro nor DrPhos' Stoichiometry shows ads.
Which is updated more often, Stoichiometry Pro or DrPhos' Stoichiometry?
Stoichiometry Pro ships an update every 4 months, and DrPhos' Stoichiometry every 3 weeks. Most recently, Stoichiometry Pro was updated on August 20, 2026 and DrPhos' Stoichiometry on September 20, 2026.

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