Math & Numbers
Compute complex impedance, magnitude |Z| and phase angle φ for series or parallel RLC circuits: X_L=2πfL, X_C=1/(2πfC), |Z|=√(R²+X²), φ=atan2(X,R). Supports any subset of R/L/C and an optional linear frequency sweep.
impedance-calculatorFinance
Project investment growth with initial principal plus monthly contributions and compound interest. Supports compounding frequency, inflation-adjusted real value, and yearly contribution escalation, with a yearly breakdown table and nominal vs real balance curves.
investment-calculatorUtilities
Estimate how many buckets of interior paint you need from room dimensions, doors/windows, coats, paint coverage, and bucket size — rounded up to whole buckets, with optional primer and waste factor.
interior-paint-coverage-estimatorUtilities
Parse SMILES, detect the senior functional group, find the longest carbon chain, and emit a teaching-oriented IUPAC name with E/Z and R/S hints.
iupac-organic-naming-toolValidation
Validate International Securities Identification Numbers (ISO 6166 ISIN) with Luhn check-digit verification, country/issuer prefix and NSIN breakdown.
isin-validatorNetwork
Visualize the geographic location, network (ASN/ISP), timezone, and security posture of any IP address as a rich card report
ip-geolocationDevelopment
Convert between natural-language durations and ISO 8601 durations (PnYnMnDTnHnMnS) in both directions with validation of edge cases
iso-8601-duration-builderAstronomy
Predict ISS, Hubble, and representative Starlink passes for a chosen observing point and date
iss-satellite-pass-trackerMath & Numbers
Convert joules to electronvolts with configurable precision
joule-to-electronvoltMath & Numbers
Convert joules to BTU with configurable decimal precision
joule-to-btuMath & Numbers
Convert joules to kilowatt-hours with configurable decimal precision
joule-to-kwhMath & Numbers
Convert joules to calories with selectable calorie standard and configurable precision
joule-to-calorie