pH Acid/Base Index

Evaluate hydrogen ion concentrations and check acidic or alkaline levels using pH logarithmic scales.

pH 7.0
Typical Substances pH reference
pH ACIDITY INDICATORS
Hydroxide [OH-]1.00e-7
Relative StatusNeutral Pure Solvent 💧

Explore Additional Utilities

Water hammer pressure — velocity ↔ pressure spike

Determine the maximum instantaneous water hammer pressure shockwave surge from sudden flow velocity shutdowns.

plumbing

Oxygen Saturation & PaO2 Converter

Convert blood oxygen saturation (SpO2) to partial pressure of oxygen (PaO2) using the clinical Severinghaus-Ellis model.

unit

Sample size calculator — confidence level ↔ margin of error

Determine required sample sizes for research surveys or experiments based on population size, confidence levels, and target margin of error.

research

Flesch-Kincaid Reading Level

Calculate readability scores and Flesch-Kincaid school grade levels for any input text in real-time.

devtools

Stride length ↔ cadence ↔ running speed

Analyze running biomechanics: calculate speed based on cadence (SPM) and stride length.

sports-science

Script Character ↔ Word Counter

Analyze characters, spaces, punctuation, words, and word density. Convert text density predictions between CJK and Latin scripts.

devtools

Weld throat thickness ↔ leg length — fillet weld geometry

Convert between throat thickness and leg length for fillet welds. Estimate joint volume, weld weight, and shear load capacity.

welding-metallurgy

IQ score ↔ percentile rank

Map IQ scores (with standard deviations 15 or 16) to cognitive percentile ranks, rarity indices, and standard intelligence brackets.

research

Board feet ↔ cubic meters ↔ cubic feet — lumber volume

Convert lumber volume measurements between Board Feet, Cubic Feet, and Cubic Meters.

woodworking

Ocean depth ↔ pressure — bar per 10 meters rule

Calculate hydrostatic and total pressure in the ocean based on depth, water density, and gravity constants.

oceanography

De Broglie wavelength — particle mass + velocity → wavelength

Calculate quantum mechanical wavelengths for matter waves under both classical and relativistic velocities.

quantum-atomic

Hood size — beak width ↔ head circumference

Determine the optimal hood size, pattern dimensions, and fitting index from a bird’s beak width and cranial circumference.

falconry

Wind power density — wind speed ↔ watts per sq meter

Calculate available wind kinetic power density (W/m²) based on wind speed and localized air density characteristics.

renewable-energy

Pattern scaling — original size ↔ scaled dimensions

Scale sewing and cutting patterns up or down uniformly. Convert dimensions between source and target sizes.

leatherworking

Thread count ↔ fabric quality rating

Calculate and convert cotton single-ply thread counts to analyze and rate fabric quality and softness.

textile-manufacturing

International Ring Size Matcher

Compare finger size rings across US, UK, Europe, and Asian dimensions.

unit

Mortar mix ratio — cement ↔ sand ↔ water by weight

Calculate standard masonry mortar mix classes (Type M, S, N, O, K) and determine precise cement, sand, and water weights.

masonry-concrete

NATO Phonetic Alphabet

Spell out commands or names phonetically using the standard military/aviation phonetic alphabet.

devtools

Responsive Font Units Converter

Compute points, pixels, em, rem web font guidelines, and equivalent font sizes.

devtools

Tsunami wave speed — ocean depth ↔ km/h

Predict shallow water tsunami wave propagation speed from ocean depth parameters.

seismology