Comparison

555 Calc vs Capacitor Calculator

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

Head to head
About

555 Calc

This utility app helps engineers and hobbyists calculate resistor values for circuits using the Timer IC 555. Simply input frequency, duty ratio, and capacitor values to get the required resistor outputs.

Highlights
  • Calculate resistor values
  • Input frequency
  • Input duty ratio
  • Input capacitor value
  • Timer IC 555 circuit design
Features
Read full description

This App calculates registors value, when designing the circuit using Timer IC 555. How to (1) Input Frequency value. (2) Input Duty Ratio. (3) Input C1 Value. (4) Touch ‘Calculate’ button. (5) Registors value will be displayed. Note. * Set Duty Ratio to 50 ~ 99. * If you set Duty Ratio to 50, R1 value will be set to 0.

About

Capacitor Calculator

This utility app calculates the time constant and energy stored in a capacitor. It helps understand the time-delay characteristics of electrical circuits when a voltage is applied.

Highlights
  • Calculate time constant (RC)
  • Calculate energy stored (E)
  • Input voltage, capacitance, and resistance
  • Understand capacitor charging/discharging
  • Analyze circuit time-delay
Features
Read full description

Capacitor Calculator is an all-in-one toolkit for students, hobbyists, technicians, and electrical engineers who work with capacitors every day. Whether you are designing an RC circuit, sizing a power supply, building a flash circuit, or studying electromagnetism for an exam, this app gives you fast and accurate answers together with the formulas and calculation steps behind every result. THREE CALCULATORS IN ONE APP 1. Capacitor Charge and Time Constant Enter supply voltage (V), capacitance (C), and series resistance (R) to instantly calculate: • Stored energy: E = 0.5 * C * V^2 • RC time constant: T = R * C • Charge stored: Q = C * V 2. Parallel Plate Capacitance Compute capacitance using plate area, separation distance, and relative permittivity with: C = e0 * er * A / d Perfect for understanding how geometry and dielectric materials affect capacitance. 3. Spherical Capacitor Calculate capacitance between two concentric conducting spheres using: C = 4 * pi * e0 * er * R1 * R2 / (R2 - R1) Choose from built-in dielectric materials including vacuum, air, paper, glass, mica, ceramic, polyethylene, polystyrene, Teflon, silicon, and water. BUILT FOR REAL WORK • Unit-aware inputs for voltage, capacitance, resistance, length, and area • Scientific notation for very small or very large values • Full calculation steps with formulas and substituted values • Copy results with one tap • Save and review calculation history • Everything runs on-device with no tracking, no account, and no internet required A POLISHED NATIVE IOS EXPERIENCE • Full Light Mode and Dark Mode support • Reference tab with physical constants, formulas, and dielectric materials table Capacitor Calculator is a focused tool for electrical engineering, electronics design, physics homework, and EE coursework. Download it once and keep professional-grade capacitor calculations in your pocket. Thanks for your support, and visit nitrio.com for more apps for your iPhone and iPad.

Screenshots

555 Calc1 screens
Capacitor Calculator4 screens

Verdict

The call

The clearest difference is price: 555 Calc at Free against Capacitor Calculator's $2.99. 555 Calc also leads on rating (4.0 vs 3.8) and iOS requirement (11.0 vs 17.6). Capacitor Calculator's advantage is ads (none vs shown). On ratings volume, update cadence, in-app purchases and device support 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

555 Calc is free to download; Capacitor Calculator costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

555 Calc holds the better App Store score, 4.0 against 3.8. Both are backed by a comparable volume of ratings — 3 and 4 respectively.

UpkeepUpdate frequency

555 Calc ships an update every 20 months, Capacitor Calculator every 29 months. The most recent releases landed on October 13, 2026 and October 27, 2026 respectively.

Scorecard5 real differences · 5 level
555 Calc versus Capacitor Calculator: the parameters behind the verdict, then further details
Parameter555 CalcCapacitor Calculator
PriceFree — better$2.99
Rating4.0 (3 ratings) — better3.8 (4 ratings)
Positive reviews50.0% of reviews—
Number of ratings34 — better
Update frequencyEvery 20 months — betterEvery 29 months
AdsYesNo — better
In-app purchasesNoNo
MonetizationAd-supported — betterPaid
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS11.0 — better17.6
Further details — not scored
Size18 MB1 MB
Age rating4+4+
DeveloperJibiki WorksNitrio

Customer experience

555 Calc

All ratings3 ratings
Positive66.7%
Neutral33.3%
Negative0.0%
Written reviews2 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

Capacitor Calculator

All ratings4 ratings
Positive75.0%
Neutral0.0%
Negative25.0%

In-app purchases

None

555 Calc

No in-app purchases

None

Capacitor Calculator

No in-app purchases

Questions

Is 555 Calc free?
555 Calc is free to download, with no in-app purchases.
Is Capacitor Calculator free?
Capacitor Calculator costs $2.99, with no in-app purchases.
Which has better reviews, 555 Calc or Capacitor Calculator?
555 Calc is rated higher. 555 Calc averages 4.0 out of 5 from 3 ratings, while Capacitor Calculator averages 3.8 from 4 ratings.
Do 555 Calc or Capacitor Calculator have ads?
555 Calc shows ads; Capacitor Calculator does not.
Which is updated more often, 555 Calc or Capacitor Calculator?
555 Calc ships an update every 20 months, and Capacitor Calculator every 29 months. Most recently, 555 Calc was updated on October 13, 2026 and Capacitor Calculator on October 27, 2026.

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