Gem & Jewelry Laboratory
Standardized carat measurements, karat alloy gold purity calculations, Troy ounce precious metal valuations, and historic UK assay hallmark decoding.
1. Gold Purity Specification
2. Alloy Material & Metallurgic Spec
Explore Additional Utilities
Angular Scales & Rotations
Convert degrees, radians, and gradians for geometric or angular rotations.
Oxygen partial pressure — altitude ↔ equivalent sea level O2 %
Determine effective oxygen percentage, barometric pressure, and oxygen partial pressure at high altitudes.
BBQ Smoking Wood Quantity Calculator
Calculate the optimal quantity of smoking wood chunks or chips needed based on meat weight and type.
Chemical Solutions Concentration
Convert chemical solutions concentration (Molarity ↔ Molality ↔ PPM) and analyze mass ratios.
Flow velocity — pipe diameter + flow rate → m/s
Calculate average fluid flow velocity from pipe size or inner diameter and volumetric flow rate values.
Marine Fuel Consumption Estimator
Estimate marine engine fuel consumption in liters per hour at given RPM values using theoretical propeller law curves.
Anchor Scope Calculator
Calculate the recommended anchor rode chain and rope lengths based on water depth, vessel height, and environmental conditions.
Angular Motor Rotation
Determine crankshaft engine RPM, radian ratios, and angular physical velocities.
Numerical aperture ↔ acceptance angle — fiber coupling
Determine light coupling capabilities, supported modes, V-numbers, and acceptance cone widths for optical optical fibers.
Audio File Size & Sample Rate
Compute uncompressed audio files size based on sample rate, bit depth, and duration.
Pipe nominal size ↔ actual OD — NPS vs DN standards
Cross-reference standard Nominal Pipe Sizes (NPS) with Diameter Nominal (DN), wall thickness, and outer diameter measurements.
Beaufort Wind Force Scale
Convert wind speed units and classify storm conditions on the official Beaufort maritime wind power scale.
Premium Rate ↔ Sum Insured
Calculate basic insurance premium rates, loading factors, and sum insured relationships (percentage, permille, and absolute values).
Ocean depth ↔ pressure — bar per 10 meters rule
Calculate hydrostatic and total pressure in the ocean based on depth, water density, and gravity constants.
Slope & Contour Profiler
Calculate typographic slope gradients, percentage slopes, and angles from elevation contour differences.
Reading & Speaking Timer
Convert total word counts to estimated reading or speaking time at standard speeds.
Heat flux — watts per square meter ↔ BTU/hr·ft²
Convert heat transfer rates per unit area between W/m², kW/m², BTU/hr·ft², and cal/s·cm².
Bleed & Margin Helper
Convert print bleed and margins, and calculate print-ready canvas sizes for offset printing.
Hijri ↔ Gregorian Calendar
Convert between Islamic Hijri calendar and standard Gregorian dates, with customized crescent visibility observation adjustments.
QR Code Generator
Instantly render plain text streams or URLs into scalable vector QR patterns complete with sizing triggers.