Comparison

Voltage Drop Pro vs Resistor Code Calculator Pro

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

Head to head
About

Voltage Drop Pro

Features
Read full description

Voltage Drop Pro calculates voltage drop per NEC 2023 Article 210.19 and 215.2 — the code sections that determine if your conductor run keeps voltage drop within acceptable limits. Works offline. No subscription. One-time purchase. WHAT IT CALCULATES - Branch circuits (210.19) and feeders (215.2) - Copper (K=10.4) and aluminum (K=17.0) conductors at 75°C - All wire sizes — 14 AWG through 500 kcmil - System voltages from 120V to 480V VERDICTS BACKED BY CODE Compares your voltage drop percentage against the NEC-recommended 3% branch/feeder max and 5% combined max. Get an instant PASS or FAIL — with the actual voltage drop, margin, and wire data shown. BUILT FOR THE FIELD No ads. No cloud. No account required. Designed for electricians who need the answer in seconds, not after a signup flow. PART OF THE FIELDMETRIC SUITE Also available: Box Fill Pro (NEC box fill) and Conduit Fill Pro (NEC conduit fill calculations).

About

Resistor Code Calculator Pro

Features
Read full description

Resistor Calculator is a practical offline toolbox for electronics students, makers, repair technicians, and engineers who work with resistors and common circuit calculations. Decode resistor color bands, convert resistance values into color bands, read SMD resistor markings, browse E-Series values, and solve everyday resistor-related circuit problems in one focused app. RESISTOR TOOLS • Decode 3, 4, 5, and 6-band resistors • Convert resistance values into color bands • Support engineering notation such as 4.7k, 4k7, 2M2, and 0R22 • Calculate tolerance, minimum, and maximum resistance • Show temperature coefficient for 6-band resistors • Reverse resistor reading direction • Copy, share, save, and reset results SMD RESISTOR CODES • Decode 3-digit and 4-digit SMD codes • Support R, K, and M notation • Support EIA-96 markings • Handle zero-ohm resistors • Convert resistance values back into suitable SMD codes • Explain decoded values clearly E-SERIES VALUES • Browse E6, E12, E24, E48, E96, and E192 values • Find the nearest standard resistor values • Compare error and tolerance ranges • Open selected values directly in resistor tools CIRCUIT CALCULATORS • Series and parallel resistance • Ohm’s Law • Voltage divider • LED current-limiting resistor • Target resistance combinations • Wheatstone bridge • Op-amp gain • Star / Delta conversion • Wire resistance • Voltage drop • Pull-up / Pull-down resistor • RC time constant LIBRARY WORKFLOW • Save calculation history • Add results to Favorites • Organize values and calculations into Projects • Export project data as CSV, JSON, or plain text • Review saved calculations later BUILT FOR DAILY ELECTRONICS WORK Resistor Calculator is designed to be fast, clear, and focused. Results update immediately as you enter values, and formulas are available when you need to understand how a calculation was made. All core calculations run on your device and the app works without an account or internet connection.

Screenshots

Voltage Drop Pro4 screens
Resistor Code Calculator Pro4 screens

Verdict

The call

The clearest difference is in-app purchases: Resistor Code Calculator Pro at none against Voltage Drop Pro's 1. Voltage Drop Pro's advantage is iOS requirement (15.1 vs 17.0). On price, ads 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

Both are free to download. Voltage Drop Pro sells 1 one-off in-app purchase. Resistor Code Calculator Pro asks for nothing beyond the download.

Scorecard2 real differences · 4 level
Voltage Drop Pro versus Resistor Code Calculator Pro: the parameters behind the verdict, then further details
ParameterVoltage Drop ProResistor Code Calculator Pro
PriceFreeFree
Update frequencyEvery 3 months—
AdsNoNo
In-app purchasesYesNo — better
DevicesiPhone, iPodiPhone, iPad
Requires iOS15.1 — better17.0
Further details — not scored
Size39 MB12 MB
Age rating4+4+
DeveloperBRUCE RAY MCCAMPBELLHa Do Thi Thu

In-app purchases

1 purchases

Voltage Drop Pro

One-time1
  • Voltage Drop Pro$2.99
None

Resistor Code Calculator Pro

No in-app purchases

Questions

Is Voltage Drop Pro free?
Voltage Drop Pro is free to download, with in-app purchases available.
Is Resistor Code Calculator Pro free?
Resistor Code Calculator Pro is free to download, with no in-app purchases.
Do Voltage Drop Pro or Resistor Code Calculator Pro have ads?
Neither Voltage Drop Pro nor Resistor Code Calculator Pro shows ads.

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