Comparison

Custom Formulas vs Numeri

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

Head to head
About

Custom Formulas

This utility app allows users to create and manage complex calculations with multiple inputs and outputs. Formulas can be linked, grouped into categories, and customized for display precision. Share your custom calculations easily via email.

Highlights
  • Multiple input/output formula support
  • Linked formulas via variable names
  • Formula categorization
  • Customizable variable display order
  • Adjustable output decimal precision
  • Email formula sharing
Features
Currently charting
Read full description

This app is easy to use, but unlike simpler apps, multiple entered values can be fed into multiple formulas and multiple output values can be displayed. The output of one formula in a group can be fed into the next by using the same variable name. Related formulas can be grouped into categories to make them easy to find. e.g. Maths formulas, Surveying formulas, Loan interest formulas etc. The order of variables displayed to the user can be changed, as can the number of decimal digits of precision shown in the output fields. You can easily share formulas with other users of the app by emailing them. Three example formulas are pre-installed with the app. In order of increasing complexity they are: slope percentage, compound interest, and point scale factor.

About

Numeri

Features
Read full description

Stop juggling numbers in your head or on scraps of paper. Traditional calculators force you to work one step at a time, erasing your context with every new entry. Numeri reimagines the calculator as a smart, interactive document, giving you a clear, editable view of your entire thought process. Numeri is a notepad that calculates. Write down your thoughts naturally, line by line, and get a live result for each step. Define a width, calculate an area, and then find the cost — all in one place. Change a single number at the top, and watch all your dependent results update instantly. It's not just about getting an answer; it's about understanding how you got there. FEATURES THAT MAKE SENSE * Live, Multiline Calculations: Every line is a new calculation with an instant result. See your entire workflow at a glance, from start to finish. * Variables: Assign names to your numbers (e.g., price = 19.99) and reuse them anywhere. Stop re-typing and start building formulas that are easy to read and modify. * Rich Function Library: Go beyond basic arithmetic with built-in functions like sqrt(), pow(), sin(), cos(), log(), and more, giving you the power to solve complex problems. * Instant Result Referencing: Use the special & variable to instantly grab the result from the previous line and continue your calculation chain seamlessly. * Comments for Clarity: Use the # symbol to add notes and context to your calculations. Your future self will thank you. * Clean and Focused Interface: A clutter-free design with a custom keyboard keeps you focused on your work. Change font size and decimal precision from the Settings tab. PERFECT FOR * Students: Lay out homework problems step-by-step for complete clarity and easier review. * Engineers & Scientists: Perform quick, back-of-the-envelope calculations without losing context. * Developers: A perfect scratchpad for testing out algorithms, logic, or financial models. * Anyone: From planning a budget to calculating project materials, Numeri makes multi-step math simple and transparent. Stop just getting answers. Start understanding them. Download Numeri today and experience math that finally makes sense. EULA: https://www.apple.com/legal/internet-services/itunes/dev/stdeula Privacy Policy: https://akh.im/numeri/privacy

Screenshots

Custom Formulas4 screens
Numeri4 screens

Verdict

The call

The clearest difference is price: Numeri at Free against Custom Formulas's $3.99. Custom Formulas's advantage is in-app purchases (none vs 2) and update cadence (every 5 days vs every 2 months). 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

Numeri is free to download; Custom Formulas costs $3.99 up front. Numeri sells 2 in-app purchases, starting at $3.99 per month. Custom Formulas asks for nothing beyond the download.

UpkeepUpdate frequency

Custom Formulas ships an update every 5 days, Numeri every 2 months. The most recent releases landed on September 18, 2026 and September 15, 2026 respectively.

Scorecard4 real differences · 7 level
Custom Formulas versus Numeri: the parameters behind the verdict, then further details
ParameterCustom FormulasNumeri
Price$3.99Free — better
Rating5.0 (1 ratings) — better
Positive reviews100.0% of reviews
Number of ratings1 — better
Update frequencyEvery 5 days — betterEvery 2 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid
Best chart rank#186 — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.4 — better16.6
Further details — not scored
Size1 MB4 MB
Age rating4+4+
DeveloperAnthony DunkAlexey Kruhlik

In-app purchases

None

Custom Formulas

No in-app purchases

2 purchases

Numeri

Subscriptions2
  • Monthly$3.991 Month
  • Yearly7 Days trial$39.991 Year

Questions

Is Custom Formulas free?
Custom Formulas costs $3.99, with no in-app purchases.
Is Numeri free?
Numeri is free to download, with in-app purchases available.
Do Custom Formulas or Numeri have ads?
Neither Custom Formulas nor Numeri shows ads.
Which is updated more often, Custom Formulas or Numeri?
Custom Formulas ships an update every 5 days, and Numeri every 2 months. Most recently, Custom Formulas was updated on September 18, 2026 and Numeri on September 15, 2026.

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