Ohmica

Offline Electronics Calculator

Free · In‑App Purchases · Designed for iPad. Not verified for macOS.

The calculator your multimeter doesn't have. Solve Ohm's Law, LED resistors, voltage drop, AWG, RC timing, PCB traces, and more — completely offline. Ohmica — The Electronics Calculator Your Multimeter Doesn't Have Most electronics calculators give you a result. Ohmica shows the result, the formula behind it, the values substituted into it, and the assumptions used. Because when you're working on a real circuit, seeing the math matters. Built for Arduino, ESP32, Raspberry Pi, makers, technicians, electronics hobbyists, and engineers, Ohmica helps you solve real-world electronics calculations quickly and confidently. WHY OHMICA • Shows the actual formula used for every calculation • Supports engineering notation such as 4k7, 100nF, and 20mA • Works completely offline • No account required • No ads • Available in English and Vietnamese Unlike generic calculators, Ohmica lets you verify the model behind the result. For example, when calculating voltage drop, Ohmica can show: Vdrop = 500 mA × 847 mΩ (AWG 14, Copper, 40 m Total Run) You can immediately see what assumptions were used. If a result doesn't match your expectation, you'll know whether the calculation is wrong or your assumptions need adjustment. CORE CALCULATORS Fundamentals • Ohm's Law • LED Resistor • Voltage Divider • Resistor Color Code Passive Components • Series / Parallel Resistance • Series / Parallel Capacitance • RC Time Constant • Capacitor Code Power & Wiring • AWG Reference • Voltage Drop • Battery Runtime • PCB Trace Width Signal & Timing • PWM & Frequency • I²C Pull-up Resistor Every calculator is designed for practical electronics work rather than classroom exercises. Whether you're designing an ESP32 project, sizing LED resistors, checking wire voltage drop, calculating RC timing, or selecting PCB trace widths, Ohmica helps you get answers without opening a browser or doing calculations by hand. HISTORY & FAVORITES • Save calculations for later • Restore previous inputs instantly • Search tools quickly • Keep frequently used calculators within easy reach OHMICA PRO Unlock advanced professional tools with a one-time purchase. Pro includes: • Logic Levels • Voltage Regulator • Power Budget • Pull-down Resistor • Export History • Future Pro calculators No subscription. No recurring fees. Pay once, use forever. If Ohmica saves you time on the bench, Ohmica Pro helps support continued development while keeping the app independent and ad-free. The calculator your multimeter doesn't have.

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The developer, Tam Trinh, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

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    Information

    Seller
    • Tam Trinh
    Size
    • 28.1 MB
    Category
    • Utilities
    Compatibility
    Requires iOS 13.0 or later.
    • iPhone
      Requires iOS 13.0 or later.
    • iPad
      Requires iPadOS 13.0 or later.
    • iPod touch
      Requires iOS 13.0 or later.
    • Mac
      Requires macOS 11.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    • English
    Age Rating
    4+
    In-App Purchases
    Yes
    Copyright
    • © Vietnova
  • Developer Website
  • Privacy Policy

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