Comparison

Compounder vs Fast Interest Calculator

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

Head to head
About

Compounder

Calculate the growth of savings and investments using compound interest. Explore how regular contributions and withdrawals impact your financial goals over time. Designed for anyone to understand and utilize the power of compounding for wealth building.

Highlights
  • Calculate compound interest
  • Flexible settings
  • Factor in periodic withdrawals
  • Factor in additional contributions
  • Easy-to-use interface
Features
Read full description

Compounder lets you easily calculate the power of compound interest to reach your financial goals—whether for savings, investments, or retirement planning. What is compound interest? Compound interest is the interest calculated on both the initial principal and the accumulated interest from previous periods. This powerful tool can make a big difference over time! Example: Imagine starting with $1,000 in savings, contributing $500 monthly at an 11% annual return. After 40 years, that account could grow to $4.38 million! Even small, regular contributions—like the average American car payment—can build lasting wealth. Features: Quickly calculate compound interest with flexible settings. Factor in periodic withdrawals or additional contributions to see how they affect your growth. Easy-to-use interface, designed for anyone wanting to understand and harness compound interest, without needing a finance background. You don’t need to be a Wall Street broker to become a millionaire. Start planning your financial future with Compounder today!

About

Fast Interest Calculator

Features
Read full description

- Calculate Equated Monthly Installments with ease. - Plan your Fixed Deposits effortlessly using the Fixed Deposit Calculator. - Simplify your financial decisions with the Tax and Tip calculator. - Convert interest rates hassle-free with the Interest Rate Converter. - Evaluate bonds with the Discounted Bond Calculator. - Control your monthly payments with the checklist module.

Screenshots

Compounder3 screens
Fast Interest Calculator4 screens

Verdict

The call

The clearest difference is iOS requirement: Fast Interest Calculator at 12.0 against Compounder's 16.0. On price, update cadence, 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.

UpkeepUpdate frequency

Compounder ships an update every 3 weeks, Fast Interest Calculator every 6 weeks. The most recent releases landed on October 17, 2026 and September 23, 2026 respectively.

Scorecard1 real difference · 9 level
Compounder versus Fast Interest Calculator: the parameters behind the verdict, then further details
ParameterCompounderFast Interest Calculator
PriceFreeFree
Rating4.8 (3.4K ratings) — better—
Positive reviews61.4% of reviews—
Number of ratings3.4K — better—
Update frequencyEvery 3 weeks — betterEvery 6 weeks
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS16.012.0 — better
Further details — not scored
Size3 MB51 MB
Age rating4+4+
DeveloperJames BevinsCamilo Ortegon

Bugs and requests

Compounder

Reported bugs

3 issues
  • Calculation issues with initial investment
  • Formatting issues on mobile devices
  • Crashes after short usage

Requested features

5 requests
  • Add percentage option for withdrawal
  • Allow adjusting periodic contributions (weekly, monthly, etc.)
  • Include daily compounding option
  • Add inflation adjustment to contributions and outputs
  • Create a widget version

Fast Interest Calculator

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Compounder

No in-app purchases

None

Fast Interest Calculator

No in-app purchases

Questions

Is Compounder free?
Compounder is free to download, with no in-app purchases.
Is Fast Interest Calculator free?
Fast Interest Calculator is free to download, with no in-app purchases.
Do Compounder or Fast Interest Calculator have ads?
Neither Compounder nor Fast Interest Calculator shows ads.
Which is updated more often, Compounder or Fast Interest Calculator?
Compounder ships an update every 3 weeks, and Fast Interest Calculator every 6 weeks. Most recently, Compounder was updated on October 17, 2026 and Fast Interest Calculator on September 23, 2026.

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