Conversions & Units
259 free conversions & units tools in the Calculators & Converters collection — every one runs in your browser with no signup and no uploads. Page 1 of 3.
Unit Converter
Convert length, weight, temperature, volume, area and speed instantly.
Unit Price Calculator
Compare price per kg, litre or item across pack sizes to find the best value.
Absorbance ↔ Transmittance / % Transmittance Converter
Convert between A, T, and %T for any spectrophotometer reading
Adjusted Body Weight Calculator
ABW for obese patients when IBW undershoots actual weight
Subject Distance & Angle of View Calculator
Find the distance needed to frame a subject of known size
Arc Flash Incident Energy & Boundary Calculator
Estimate arc flash incident energy and the arc-flash boundary using the IEEE 1584 Lee method
Axle Weight & Load Distribution Calculator
Check axle weight compliance for a loaded semi-truck configuration
Bed Tramming Angle Calculator
Calculate bed tilt angle and the knob turns needed from corner probe data
Beer Dissolved CO2 & Degassing Calculator
Calculate CO2 dissolved in beer at any temperature and pressure
Mash Enzyme Activity Temperature Guide
Find optimal temperature ranges for alpha and beta amylase activity
Brooder Temperature Guide for Chicks
Calculate recommended brooder temperature by week of age for layer and broiler chicks
Building Energy Performance Rating Estimator (EPC/DEC)
Estimate a building's energy rating band from consumption and floor area
Cambridge International Grade Converter
Convert Cambridge IGCSE and A-Level grades to other systems
Camera Motion Blur & Shutter Speed Threshold Calculator
Find the slowest hand-held shutter speed before camera shake blurs the shot
Flash Sync Speed & HSS Calculator
Determine if High Speed Sync is needed and estimate HSS power loss
Air Freight Chargeable Weight Calculator
Determine air freight chargeable weight using IATA volumetric divisor 6000
Chinese Sexagenary Cycle Converter
Find the Heavenly Stem and Earthly Branch for any Gregorian year
Cholesterol Unit Converter (mg/dL to mmol/L)
Convert cholesterol and lipid values across unit systems
Climbing Grade Converter
Convert climbing grades between Yosemite, French, and UIAA.
Climbing Weekly Volume Calculator
Quantify your climbing training volume in AU (Arbitrary Units)
International Clothing Size Chart
Convert clothing sizes between US, UK, EU, and international standards
CO2 Regulator Pressure Guide
Interpret high and low gauge readings and estimate remaining CO2 in the tank
CO2 Tank Pressure vs Temperature Chart
Find expected CO2 tank pressure at any storage temperature
Countdown Target Date Converter
Convert a future date into a live countdown in days, hours, and minutes
Cycling Speed vs Power Calculator
Calculate the power needed to hit your target cycling speed.
Cycling Tyre Pressure Calculator
Calculate optimal tyre pressure from rider weight and tyre width.
Gregorian ↔ Julian Calendar Converter
Convert dates between the Gregorian and old Julian calendar
Decoction Volume Calculator
Work out how much mash to pull and boil to step up to the next rest.
DELE Spanish Proficiency Score Converter
Convert DELE exam score to CEFR level for Spanish.
DELF/DALF Score to CEFR Converter
Convert your DELF or DALF French exam score to CEFR level.
Dovetail Angle & Layout Calculator
Calculate pin-to-tail ratio, angles, and baseline spacing for hand-cut dovetails
Drainage Fixture Unit (DFU) Calculator
Total drainage fixture units and size horizontal drains and stacks per IPC Table 709.1
Drill Point Angle Calculator
Determine drill-point cone depth and geometry for any angle and diameter
Drug Dose by Weight Calculator
Calculate weight-based drug doses in mg/kg or mcg/kg for any patient
Duolingo English Test Score Converter
Convert your Duolingo English Test score to IELTS and TOEFL
Enclosure Temperature Calculator
Estimate required enclosure temperature to prevent ABS/ASA/PC warping
Enzyme Unit Activity Calculator
Calculate enzyme units (U/mL and U/mg) from a spectrophotometric assay
EQ Bandwidth to Q Factor Converter
Convert between octave bandwidth and Q factor for parametric EQ.
Estimated Blood Volume Calculator
Estimate total blood volume from weight and patient type
FDM Bridging Distance Limit Calculator
Estimate the longest unsupported bridge a material and cooling can span
Feeds & Speeds Calculator
Calculate optimal feed rate from chip load, flutes, and spindle RPM
Fermentation Temperature Effect on FG
Estimate how fermentation temperature shifts final gravity and ester production
Filament Drying Time & Temperature Calculator
Get the right drying temperature and duration for wet 3D printing filament
Filament Length to Weight Converter
Convert between filament length in meters and weight in grams
Bass Length-to-Weight Calculator
Estimate largemouth and smallmouth bass weight from a measurement
Fish Weight Estimator by Length & Species
Estimate live fish weight from length using species formulas
Fishing Barometric Pressure Activity Predictor
Predict fish activity levels from barometric pressure and trend
Focal Length Equivalence Table
Compare focal lengths across full-frame, APS-C, MFT, and medium format
EQ Frequency to Note Name Converter
See which musical note corresponds to any EQ frequency band
Fuel Economy by Trip Calculator
Calculate actual MPG, fuel cost, and CO2 from any trip distance and fill-up
Fuel Gas Pressure Drop Calculator (NFPA 54)
Verify pressure drop through a gas run stays within 0.3 in WC for low-pressure systems.
Gas Fee gwei → USD Converter
Convert Ethereum gas fees from gwei to USD and ETH in real time
Blood Glucose Unit Converter (mg/dL to mmol/L)
Instantly convert blood glucose between mg/dL and mmol/L
Goethe-Zertifikat Score to CEFR Converter
Convert your Goethe-Zertifikat German exam score to CEFR.
Grain Test Weight & Moisture Corrector
Adjust grain test weight and bushel weight to standard moisture for marketing
Haematocrit ↔ Haemoglobin Converter
Estimate Hb from HCT or HCT from Hb using the rule of three
Gregorian ↔ Hebrew Date Converter
Convert calendar dates to/from the Hebrew lunisolar calendar
Home Energy CO2 Calculator
Estimate your household's annual carbon footprint from energy use
Hop AAU (Alpha Acid Units) Calculator
Calculate AAU and HBU from hop weight and alpha acid percentage
Evaporator / Condenser Coil Airside Pressure Drop Calculator
Estimate coil pressure drop in inches WC from face velocity and coil rows
Makeup Air Unit (MAU) CFM Calculator
Size makeup air CFM to replace exhaust and hold building pressurization
Refrigerant Pressure-Temperature (PT) Chart
Look up saturation temperature from gauge pressure for R-22, R-410A, R-32, R-134a, R-404A, R-407C, R-454B
Hydrometer Temperature Correction
Correct hydrometer gravity readings taken at non-calibration temperatures.
Hz to Musical Note Converter
Identify the closest musical note and cents deviation for any frequency
IB to UCAS Tariff Points Converter
Convert your IB Diploma grades to UCAS tariff points
IBAN Length by Country
Check the correct IBAN length and format for any country
Ideal Body Weight Calculator (Devine & Robinson)
Calculate IBW for drug dosing and ventilator management
IELTS to CEFR Level Converter
Convert IELTS band scores to CEFR language levels.
ISA Temperature & Deviation Calculator
Find the standard ISA temperature at altitude and your ISA deviation
Gregorian ↔ Hijri Date Converter
Convert between Gregorian and Islamic Hijri calendar dates
Container VGM (Verified Gross Mass) Calculator
Calculate and document container VGM per SOLAS regulation for export declarations
ISO 50001 Energy Management Readiness Checker
Self-assess ISO 50001 energy management system readiness before certification
Julian Day Number Converter
Convert Gregorian dates to and from integer Julian Day Numbers
Temperature Unit Converter (°C / °F / K)
Instantly convert between Celsius, Fahrenheit, and Kelvin
Lacto Pitch Temperature Calculator
Find optimal Lactobacillus pitch temperature for sour beer production
MIDI Note Number Converter
Convert between MIDI note numbers, note names, and Hz frequencies
Miniature Scale Converter
Convert real-world dimensions to any miniature scale (28mm, 1/72, HO, N)
MMA Weight Class Finder
Find the correct MMA weight class for any fighter's walk-around weight
Oral Morphine to Fentanyl Patch Converter
Convert daily oral morphine to a transdermal fentanyl patch strength
Mortar Mix & Volume Calculator
Calculate bags of mortar or dry-mix components for any masonry job
Nasogastric Tube Insertion Length Estimator
Estimate NG tube insertion depth from height as a placement starting point
Nozzle Temperature by Material Lookup
Find recommended nozzle and bed temperatures for any 3D printing material
Number to Ordinal Converter
Append ordinal suffixes: 1st, 2nd, 3rd, 4th…
Number to Words Converter
Spell out any integer in English words (one, two, three…)
Opioid MME Converter (Morphine Milligram Equivalents)
Convert any opioid dose to morphine equivalents for safe comparison
Paediatric Tidal Volume & Ventilator Settings Calculator
Weight-based ventilator tidal volume for lung-protective ventilation
Parcel Cost-Per-Unit Calculator
Compare shipping cost per unit across different parcel pack configurations
PCR Annealing Temperature Optimizer
Suggest an annealing temperature from primer pair Tm values
Color Temperature & White Balance Calculator
Convert between Kelvin, Mired shift, and white balance preset names
Pipe Schedule & Pressure Rating Calculator
Find pipe wall thickness, weight, and working pressure for any schedule and size
Plato / Brix / Specific Gravity Converter
Instantly convert between °Plato, Brix, and specific gravity
Plumbing Fitting Angle & Rolling Offset Calculator
Solve rolling offsets for pipe runs moving simultaneously horizontal and vertical.
Weld Preheat & Interpass Temperature Calculator
Calculate carbon equivalent and minimum preheat for steel per AWS D1.1
Pressure Altitude Calculator
Convert altimeter setting and indicated altitude to pressure altitude
Print Bed PID Temperature Calculator
Estimate PID parameters for stable print bed temperature control.
Print Orientation & Support Volume Estimator
Compare support volume and print time across different print orientations.
Print Speed vs Quality Tradeoff Calculator
Find the max FDM speed before quality drops for your printer and material
RC Helicopter Blade Pitch & Head Speed Calculator
Find the gear ratio, head speed, and collective pitch for your RC heli
RC Servo Torque & Horn Length Calculator
Calculate required servo torque for any control surface or mechanism
Centrifuge RCF / RPM Converter
Convert between relative centrifugal force and revolutions per minute