Compounder vs Fast Interest Calculator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- Calculate compound interest
- Flexible settings
- Factor in periodic withdrawals
- Factor in additional contributions
- Easy-to-use interface
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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!
Fast Interest Calculator
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- 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
Verdict
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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
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.
| Parameter | Compounder | Fast Interest Calculator |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (3.4K ratings) — better | — |
| Positive reviews | 61.4% of reviews | — |
| Number of ratings | 3.4K — better | — |
| Update frequency | Every 3 weeks — better | Every 6 weeks |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 16.0 | 12.0 — better |
| Further details — not scored | ||
| Size | 3 MB | 51 MB |
| Age rating | 4+ | 4+ |
| Developer | James Bevins | Camilo 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
Compounder
No in-app purchases
Fast Interest Calculator
No in-app purchases
Questions
Is Compounder free?
Is Fast Interest Calculator free?
Do Compounder or Fast Interest Calculator have ads?
Which is updated more often, Compounder or Fast Interest Calculator?
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