A 4-band resistor uses two digit bands plus a multiplier plus a tolerance band. A 5- or 6-band resistor adds a third digit for extra precision, and a 6-band adds a temperature coefficient (PPM/°C) band for how much the resistance drifts with heat. More bands generally means a more precise, more temperature-stable part.
The tolerance band color tells you how far the real resistance can vary from the printed value — gold is ±5%, silver is ±10%, brown is ±1%, and so on. A tighter tolerance (smaller %) usually means a more expensive, more precise resistor.
If you know the resistance you need but not the color bands to look for, Encode mode does the reverse lookup — enter a target value and it snaps to the nearest real E24 or E96 series resistor and shows the band colors to look for on the shelf.
Surface-mount resistors are too small for color bands, so they use printed numeric codes instead: a 3-digit code (like 103) treats the last digit as a multiplier for the first two, a 4-digit code adds precision, "R" marks a decimal point (4R7 = 4.7 Ω), and EIA-96 codes combine a 2-digit lookup value with a letter multiplier. SMD mode decodes all of these.
Sorting or checking a whole parts bin one resistor at a time is slow. Batch mode decodes a whole list at once — one resistor per line, mixing color-band and SMD-code formats freely — useful when auditing inventory or verifying a bill of materials.
Decode Mode: Read resistor color bands and instantly get the resistance value, tolerance, and acceptable range.
Encode Mode: Find the correct color band sequence for a target resistance value using standard series.
SMD Mode: Decode surface-mount resistor codes (3-4 digit markings) quickly and accurately.
Batch Mode: Process multiple resistor values at once — perfect for quality control and rapid testing.
Component Reading: quickly decode resistor color bands on circuit boards, verify component values during assembly or repair, and avoid costly mistakes from misread resistance values.
Design & Selection: find resistor color bands for a target resistance value, select from E24 or E96 series for availability, and match tolerance requirements for precision circuits.
SMD Component Identification: decode surface-mount resistor codes quickly, identify unmarked components with code lookup, and verify SMD values in automated assembly.
Batch Testing: process resistor values from quality control data, generate reports for component verification, and sort resistors by series and tolerance.
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