4–20 mA Level Calculator
Convert 4–20 mA signals to level, calculate expected five-point readings, compare observed values and determine the current for a level setpoint.
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All Zacdaddy Tools
Every free calculator, converter and utility from Zacdaddy Tools, organised alphabetically so you can find the right one quickly.
33 tools found
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A
Age Calculator
Calculate exact age between two dates in years, months and days, plus total weeks, total days and the next birthday. Free and instant.
Open toolAspect Ratio Calculator
Calculate a simplified aspect ratio or resize image and video dimensions while preserving proportions. Includes common ratio presets.
Open toolB
Best Value & Unit Price Calculator
Compare prices across different pack sizes, quantities and units. Rank items, weight or volume options by unit cost to find the best value.
Open toolBMI Calculator
Calculate adult BMI in metric or imperial units, see the standard weight category and view a healthy weight range for your height.
Open toolC
Carpet Area Calculator
Measure carpet for rectangular and awkward rooms by combining multiple areas. Add a waste allowance and convert between square metres and feet.
Open toolCase Converter
Convert text to uppercase, lowercase, title case, sentence case, camelCase, PascalCase, snake_case or kebab-case in your browser.
Open toolCompound Interest Calculator
Calculate how savings or investments could grow with compound interest and regular monthly contributions. Free compound interest calculator with yearly breakdown.
Open toolConcrete Calculator
Free UK concrete calculator for slabs, shed bases, paths, footings, trenches, round bases and post holes. Calculate m³, litres, bag quantities and cost.
Open toolCurrency Converter
Convert GBP, EUR, USD and other currencies using the latest available reference exchange rates. View inverse rates and the published rate date.
Open toolD
Date Difference Calculator
Calculate exact time between two dates in years, months and days. See total days, full weeks, weekdays and weekends, with optional end-date inclusion.
Open toolDiscount Calculator
Calculate sale prices, cash savings and effective discounts. Apply one or two discounts and compare results in pounds, dollars or euros.
Open toolE
Electricity Running Cost Calculator
Estimate appliance electricity use and running costs per day, week, month and year from wattage, usage time and your tariff.
Open toolF
Fuel Cost & Trip Calculator
Estimate fuel needed and journey cost from distance, vehicle efficiency and pump price. Include return trips and split costs between passengers.
Open toolJ
JSON Formatter & Validator
Format, minify and validate JSON instantly with clear syntax errors. Free, private browser-based JSON tools with no upload required.
Open toolL
Loan Repayment Calculator
Estimate monthly loan repayments, total interest and payoff time. Add an extra monthly payment to see potential time and interest savings.
Open toolP
Paint & Decorating Calculator
Estimate paint for multiple walls and surfaces. Deduct doors and windows, choose coats, coverage and wastage, and get litres to buy.
Open toolPassword & Passphrase Generator
Generate cryptographically random passwords and memorable passphrases in your browser. Choose length, character types, words and separators.
Open toolPercentage Calculator
Calculate a percentage of a number, find what percentage one value is of another, or measure percentage increases and decreases.
Open toolPercentage Difference Calculator
Compare two values symmetrically and calculate their percentage difference, absolute difference and average, with clear handling of zero values.
Open toolProfit Margin & Markup Calculator
Calculate profit, margin and markup from cost and selling price, or find the selling price required for a target margin or markup.
Open toolQ
QR Code Generator
Create a QR code for a website address or text. Customise colours, size and error correction, then copy or download PNG and SVG files.
Open toolR
Random Number Generator
Generate up to 100 cryptographically random whole numbers within a custom range, with an option to prevent duplicate results.
Open toolRegex Tester
Test JavaScript regular expressions, flags and matches instantly. Free browser-based regex tester with clear highlighting and validation.
Open toolS
Salary to Hourly Pay Calculator
Convert gross annual, monthly, weekly, daily and hourly pay using your own paid weeks, working days and weekly hours.
Open toolT
Text Diff Checker
Compare two blocks of text and instantly highlight additions, deletions and changed lines. Free browser-based text diff checker with no uploads.
Open toolTime Duration Calculator
Calculate elapsed hours and minutes between two times, including overnight periods, total minutes and optional break deductions.
Open toolTip Calculator & Bill Splitter
Calculate a tip, total bill and amount per person. Choose a preset or custom percentage and split the bill between up to 100 people.
Open toolU
UK VAT Calculator
Free UK VAT calculator. Add VAT to a price, remove VAT from a total and see the VAT amount instantly. Simple, fast and easy to use.
Open toolUnit Converter
Convert length, area, volume, weight, temperature, speed, pressure, energy and power units instantly in your browser.
Open toolUUID / GUID Generator
Generate UUID v4 identifiers instantly in your browser. Create one or many UUIDs or GUIDs, change the format, copy results and download them.
Open toolW
Word & Character Counter
Count words, characters, characters without spaces, sentences and paragraphs as you type, with an estimated reading time.
Open toolWorking Days Calculator UK
Count working days between two dates in England and Wales, Scotland or Northern Ireland, excluding weekends and UK bank holidays.
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