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電子回路の計算を直感的かつ正確に。国際規格に完全準拠したオープンな技術ツールを提供します。
Our Mission
STANDARDIZED • ACCESSIBLE • OPEN SOURCE
OhmColorCode.com was built to solve a simple yet ubiquitous problem faced by electrical engineers, hardware technicians, STEM students, and electronics hobbyists: quickly, accurately, and reliably decoding resistor color codes and SMD marking codes without clunky apps, invasive trackers, or paywalls.
Every calculation on OhmColorCode.com is processed entirely client-side using mathematically verified lookup algorithms conforming strictly to the International Electrotechnical Commission (IEC) and Electronic Industries Alliance (EIA) specifications.
International Standards Compliance
Our calculators and tables are calibrated directly to published global engineering standards:
Standardized color markings for 3-band, 4-band, 5-band, and 6-band axial lead resistors. Governs significant digit assignments, logarithmic multiplier powers of ten, tolerance percentages (from ±0.05% to ±20%), and temperature coefficient (TCR) values.
Standard preferred number series for resistors and capacitors. Our calculators validate decoded values against decade steps in the E6 (20%), E12 (10%), E24 (5%), E48 (2%), E96 (1%), and E192 (0.5%) standard component series.
Decoding for modern 1% tolerance surface-mount resistors (SMD 0603, 0805, etc.) using two numeric digits for the base value and an alphabetic multiplier letter (e.g., 01C = 10 kΩ, 68X = 4.99 Ω).
Real-time electrical formulas for Voltage (V = I · R), Current (I = V / R), Power Dissipation (P = V · I = I² · R), and reciprocal calculations for parallel resistor arrays (1/R_total = 1/R1 + 1/R2 + ...).
What Sets OhmColorCode Apart
Instant, Zero-Latency Calculations
No page reloads or API latency. All color band rendering, SVG updates, tolerance min/max calculations, and reverse conversions execute instantaneously in your browser.
Colorblind Assist & High Contrast
We provide explicit tactile color labels, high-contrast markers, and colorblind mode (Alt+A) to ensure that red/brown, orange/yellow, and green/grey bands are never confused.
Zero Tracking & Complete Privacy
We respect your digital privacy. We don't ask for accounts, don't use tracking cookies, and never monetize personal user data.
Technology & Open Standards
OhmColorCode.com is built with cutting-edge web technologies: Astro for static generation, Tailwind CSS v4 for styling, and vanilla TypeScript for rock-solid calculation routines. It ships near-zero client-side bundle weight, loads in milliseconds globally via edge CDNs, and works seamlessly offline.