Resistor Color Code & SMD Calc

Read any resistor in seconds. Tap the bands you see, get the resistance, tolerance and range instantly — or type a value and get the color code back. Works completely offline, with no account and no sign-up.

Built on IEC 60062:2016, the standard the color code is actually defined by, and checked against reference tables in automated tests. Accuracy is the whole point of a tool like this.

RESISTOR COLOR CODE
• 3, 4, 5 and 6 band resistors, including the temperature coefficient band
• Live result while you pick the bands — resistance, tolerance, min/max range
• Value to color code: enter 4k7, 4.7k or 4700 and see every valid band layout at once
• 0 Ω jumpers, gold and silver multipliers, all tolerance bands
• Long-press a color for its name, IEC letter code and digit
• The result is always repeated as plain text, so you can read it out or copy it

SMD RESISTOR CODES
• 3-digit and 4-digit codes
• EIA-96 — all 96 codes with their letter multipliers
• R-notation (4R7) and jumper codes
• Backwards too: enter a resistance, get every SMD code that produces it

E-SERIES
• E3, E6, E12, E24, E48, E96 and E192
• Tells you whether your value is a standard one, and shows the nearest standard values when it is not

ELECTRONICS CALCULATORS
• Ohm's law — fill in any two of voltage, current, resistance and power
• LED series resistor, with the nearest standard value and the power it will dissipate
• Voltage divider, including a suggested R1/R2 pair
• Power derating check against the rated wattage
• Series and parallel combinations, plus a target finder that searches pairs for the value you actually need
• Inductor color code in µH, including the military spec variant

LEARN AND PRACTICE
• Reference articles: how to tell which end to read from, what each band means, tolerance and temperature coefficient tables, the full EIA-96 table
• Practice quiz with 10-question rounds, best score and streak, and a review of the ones you got wrong

BUILT FOR THE BENCH
• Colorblind mode: every band labelled with its color name, so nothing depends on telling brown from red
• Optional blue (1%) resistor body instead of beige
• Light and dark themes, or follow the system — dark is kinder next to a soldering iron
• Haptic feedback on every band you pick, with a switch to turn it off
• History of your last 50 calculations, plus a Saved list where you can label entries ("R14 on the PSU board")
• Compare with a real resistor: a live camera preview next to the drawn one, with flashlight, zoom, tap to focus and a freeze button. It is a visual comparison you make with your own eyes — nothing is scanned or auto-detected, because guessing colors from a photo is exactly how these tools get it wrong
• 30+ languages: English, German, Spanish, French, Italian, Portuguese, Russian, Polish, Turkish, Japanese, Korean, Chinese, Hindi, Arabic and more

PERMISSIONS
Internet is used for ads only. The camera permission is asked for the first time you open the camera comparison, and never otherwise — refuse it and everything else keeps working. Nothing you enter leaves your phone.

For students, hobbyists, repair techs and anyone building with Arduino, Raspberry Pi or ESP32 who is tired of squinting at four faded stripes.

Questions or a bug to report: zoryatechstudio@gmail.com