// the free-tools network
Free tools, no signups, no nonsense
totalinterestcalc.com is one of 52 independent tools built and maintained by the same maker. Each does a single job well, runs in your browser, and works without an account.
What every tool in the network promises
Calculators & Everyday
Square Footage Calculator
thesquarefootagecalculator.comArea, flooring and material calculators for any space.
Percentage Calculator
bestpercentagecalculator.netEvery percentage problem: increase, decrease, of, change.
Age Calculator
theagecalculator.netExact age, birthday twins, and date-difference tools.
Hours Calculator
calculatehours.netTime between clock-ins, timesheets, and work hours.
World Clock
clockwithus.comCurrent time across cities and time zones.
Unit Cheat Sheet
unitcheatsheet.comFast unit conversions with printable reference sheets.
Box Volume Calculator
boxvolumecalculator.comVolume, dimensions and capacity for boxes and containers.
Girth Calculator
girthcalculator.comParcel girth for shipping plus fitness measurements.
CaloriesKit
calorieskit.comTDEE, calorie and macro calculators with honest activity inputs.
BMI & BMR Calculator
bmibmrcalc.comBody mass index and basal metabolic rate in seconds.
Fraction Calculator
fractionsteps.comAdd, subtract and divide fractions with step-by-step working.
GPA Calculator
gpacalculatorhq.comCalculate GPA and CGPA from grades and credit hours.
Tank Volume Calculator
tankvolumecalc.comVolume and fill level for tanks of any shape.
Pool Volume Calculator
poolvolumecalc.comPool water volume in gallons or litres, any shape.
Cubic Yardage Calculator
cubicyardage.comCubic yards of concrete, gravel, mulch and soil.
Concrete Material Calculator
concretematerialcalc.comConcrete, cement, sand and aggregate for slabs and footings.
Roofing Material Calculator
roofingmaterialcalc.comEstimate shingles and materials by roof area and pitch.
Stair Calculator
staircalculators.netStair rise, run, stringer length and step count to code.
Construction Calculators
constructioncalchq.comA hub of construction calculators for materials and estimates.
Cooking Measurement Converter
measurechef.comConvert cups, grams, ounces and spoons for any recipe.
Finance & Business
Margin vs Markup
marginvsmarkup.comPricing calculators that keep margin and markup straight.
India EMI Calculator
indiaemi.comLoan EMI, eligibility and amortization for Indian borrowers.
Dimensional Weight Calculator
dimweightcalc.comDim weight across 17 carriers — know your billable weight.
Pro Solar Calculator
prosolarcalc.comSolar sizing, savings and payback estimators.
Voltage Drop Calculator
voltdropcalc.comElectrical voltage drop, wire sizing and NEC references.
SIP Calculator
sipcalculatorhub.comProject mutual fund SIP returns by rate, tenure and step-up.
Solar Battery Bank Calculator
solarbatterybankcalc.comSize a solar battery bank by load and days of autonomy.
Backup Power Calculator
backuppowercalc.comSize a generator or battery backup by wattage and runtime.
AC Tonnage Calculator
actonnagecalc.comSize an air conditioner in tons from room area and climate.
Developer Tools
Base64 Encode / Decode
base64decode.toolsEncode and decode Base64 text and files in the browser.
URL Encode / Decode
urlencodedecode.comPercent-encoding for URLs, queries and components.
UUID Generator
www.uuidcore.comBulk UUID/GUID generation, all versions.
JSON Tools
jsontools.toolsFormat, validate, repair and explore JSON with a tree view.
Hash Generator
hashgenerator.toolsMD5, SHA-1/256/512 and more, computed client-side.
Epoch Time Converter
epochtime.toolsUnix timestamps to dates and back, with code snippets.
Crontab Cheat Sheet
crontabsheet.comCron expressions explained, built and validated.
Regex Guide
regexguide.comLearn, test and reference regular expressions.
Transform Case
transformcase.comConvert text between cases: camel, snake, title and more.
Text Repeater
textrepeat.netRepeat and join text patterns for testing and content.
Color Code Kit
colorcodekit.comOKLCH-native color tokens, palettes and WCAG contrast.
CIDR Calculator
cidrcalculator.netCIDR blocks, ranges and subnet math for network engineers.
Subnet Mask Calculator
subnetmaskcalc.netSubnetting, masks and host ranges with code examples.
Number to Words
numtotext.comConvert numbers to words for cheques and invoices.
Internet Speed Test
checkinternetspeed.toolsTest download, upload and ping speed in the browser.
What Is My IP
checkmyipnow.comSee your public IP, location, ISP and browser.
WHOIS Lookup
whoislookuppro.comDomain registration, ownership, expiry and DNS records.
Text, Files & Privacy
Word Counter
wordcounterfree.comWords, characters, sentences and reading time, instantly.
Password Strength
passwordstrength.netTest password strength locally — nothing is transmitted.
Pic Toolkit
pictoolkit.comPrivacy-first image converting, resizing and editing.
Remove Metadata
removemetadata.toolsStrip EXIF and metadata from files entirely in-browser.
Core PDF Tools
corepdftools.comMerge, split, compress and convert PDFs client-side.
Barcode & QR Generator
barcodeandqr.comGenerate barcodes and QR codes with PDF export.