Voltary

Voltary is the offline electronics bench that lives in your pocket — a fast, private toolkit of calculators, connector pin-outs, reference tables and a schematic sketchpad, built for engineers, students, makers and repair techs. No account, no sign-up, no internet required. Everything works on the bench, in the field, or on a plane.

WHY "OFFLINE"?
Every feature in Voltary runs entirely on your device. All calculators, pin-out diagrams, reference tables and the sketchpad are built into the app and computed locally — so the app needs no internet connection, no server and no account to do its job. You can use the whole app in Airplane Mode. (The only optional network use is ads; they are never required to use any tool.)

FREE — NO PAID FEATURES
Voltary is completely free. There are no in-app purchases, no subscriptions and nothing locked behind a paywall — every tool, table and diagram is fully available to everyone. The app is simply supported by ads.

CALCULATORS & CONVERTERS (40+)
Solve the everyday electronics math in seconds — enter any values and Voltary computes the rest, in clean engineering notation with proper SI prefixes.
• Ohm's law, power & dissipation
• LED series resistor, voltage divider, Zener
• Reactance & resonance, RC/RL/LC filters
• 555 timer, LM317 regulator, op-amp gain
• Capacitor charge, series/parallel R & C
• Inductor design, Y-Δ transform, RTD/PT100
• Battery life, voltage drop, PCB trace width
• Resistor & inductor colour-code decoders
• SMD code lookup, dB, number-base & unit converters
Long-press a result to send a value straight into another tool — no retyping.

PIN-OUTS (39 connectors, real diagrams)
Stop hunting through datasheets. Voltary ships accurate, colour-coded pin-outs you can tap and zoom:
• USB Type-A & Type-C, HDMI, DisplayPort, VGA
• Ethernet RJ-45 (T568B), SATA, ATX power
• Raspberry Pi 40-pin GPIO, GPIB and many more
Pins are grouped by function (power, ground, data, clock) so wiring is obvious at a glance.

REFERENCE LIBRARY
A built-in shelf of the tables you keep looking up:
• SI unit prefixes, E12/E24 standard values
• AWG wire size, PCB resistivity
• IP ingress-protection codes
• Logic-gate truth tables, ASCII table
• Blade-fuse colours, battery types
• SMD package sizes, 7400-series logic
• A searchable schematic-symbol gallery

SCHEMATIC SKETCHPAD
Capture an idea before it's gone. Drop components, route wires, add labels and text on an infinite grid, then save your sketches or share them as a PNG.

BUILT FOR REAL WORK
• 100% offline — every tool, table and diagram is on-device
• Free, with no in-app purchases or subscriptions
• Engineering notation with tabular figures (no jittering columns)
• Light & dark themes, edge-to-edge modern design
• Fast, native, and respectful of your data
• Available in 14 languages: English, Spanish, Portuguese, Arabic, French, German, Russian, Hindi, Indonesian, Turkish, Japanese, Korean, Simplified Chinese and Italian — including full right-to-left layout

PRIVATE BY DESIGN
Voltary doesn't ask you to create an account and doesn't need the network to do its job. It's a tool, not a service.

Whether you're sizing a current-limiting resistor, wiring a USB-C connector, checking an AWG rating or sketching a quick circuit, Voltary puts the whole bench one tap away.

Download Voltary and keep your electronics reference, math and notes in one place — always offline, always ready.