Electra - Electronics Toolkit
Learn, Calculate & Take Notes
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Your pocket toolkit for electronics engineering. Decode resistors, calculate Ohm's Law, design filters, and take notes — all offline, no sign-in required.
Electra is a fast, offline-first electronics reference tool built for engineers, students, hobbyists, and makers.
Whether you're on the bench or in the field, Electra puts every essential calculation and reference at your fingertips - no internet connection required.
CALCULATORS
- Resistor Decoder: Read 4-band and 5-band color codes instantly
- Ohm's Law: Solve for voltage, current, resistance, or power
- LED Resistor: Calculate the correct current-limiting resistor
- SMD Decoder: Decode capacitor and inductor SMD markings
- Voltage Divider: Solve any variable in a resistor divider network
- Battery Calc: Estimate capacity and discharge time
- Resistor Network: Series and parallel combination solver
- RC / LC Filter: Cutoff frequency calculator for RC and LC circuits
- 555 Timer: Astable and monostable mode frequency calculator
- Voltage Regulator: LM317 output voltage calculator
REFERENCE
- Symbol Guide: Common electronics schematic symbols
- E-Series Values: Standard E6 / E12 / E24 / E96 component tables
- Formula Sheet: Quick-access electronics formulas
UTILITIES
- Base Converter: Convert between Binary, Octal, Decimal, and Hex
- Unit Converter: Instantly convert electronics unit prefixes (u, m, k, M, G)
LEARN
- Notes: Save tagged notes for formulas, tips, and component specs
- History: Jump back to any recent calculation in one tap
CUSTOMIZE
- Light, Dark, or System theme
- Adjustable decimal precision (1 to 6 places)
Electra requires no account, collects no personal data, and works fully offline.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Ina okviana Risyadi, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Ina okviana Risyadi
- Size
- 23.3 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Electra.