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Data-driven hubs with a dedicated page per model, city, year, or event.
Event Countdowns
Countdowns to holidays and events
84 eventsAI Coding Cost
What every dollar of AI coding spend actually buys you, model by model
25 modelsGerman School Holidays
Countdowns and bridge days for all German states
264 eventsGerman Bridge Days Planner
Turn a few vacation days into long weekends — every German state, 2026–2030
80 plannersSteam Games
Revenue estimates for popular Steam games
2472 gamesHouseplant Care
Watering calculator, light & pet-safety for 600+ plants
647 plantsGerman Civil Servant Salary
Beamtenbesoldung by German state and grade, with comparison
214 pagesGerman Parental Leave Planner
Financial planning for German civil servants on parental leave
51 scenariosCompound Interest Examples
See how amounts from $500 to $1M grow over time
14 amountsGerman Property Tax Calculator
2025 German property tax (Grundsteuer) by city Hebesatz
20 citiesCup Conversions
Cups to grams, ounces, ml — per ingredient
15 ingredientsVolume Conversions
Cups to ounces, ml, tablespoons & more
14 conversionsCalories Burned
How many calories any activity burns
78 activitiesLength Conversions
Inches, feet, cm, mm, meters & miles
22 conversionsWeight Conversions
Kilograms, pounds, grams, ounces & stone
20 conversionsArea Conversions
Square feet, meters, acres, hectares & miles
22 conversionsSpeed Conversions
mph, km/h, knots, m/s & ft/s
16 conversionsDog Tax Germany
Annual dog tax (Hundesteuer) by German city
200 citiesTemperature Conversions
Celsius, Fahrenheit & Kelvin
6 conversionsPower Conversions
Kilowatts, horsepower, PS & watts
16 conversionsData Storage Conversions
GB, MB, KB, TB, bytes & bits
16 conversionsEnergy Conversions
Joules, kWh, kcal, calories & BTU
16 conversionsBoard Game Score Keeper
Score keeper & calculator for 100+ board games
115 gamesGerman Retirement Planner
German pension by birth year — statutory, civil servants, survivors
65 cohortsBinge-Watch Time
How long to binge any TV series — runtime & finish date
1040 seriesPressure Conversions
psi, bar, kPa, atm & mmHg
16 conversionsFrequency Conversions
Hz, kHz, MHz, GHz, rpm & rad/s
16 conversionsAngle Conversions
degrees, radians, gradians, arcmin, arcsec & turns
16 conversionsFuel Economy Conversions
mpg, L/100km & km/L — US and imperial gallons
12 pairsRunning Pace Conversions
min/km, min/mile, km/h & mph — pace ↔ speed
10 pairsData Rate Conversions
Mbps, MB/s, Gbps, kbps & more
16 conversionsTime Conversions
Seconds, minutes, hours, days & weeks
16 conversionsAP Score Calculators
Predict your 1–5 on every AP exam
26 examsCurrency Conversions
USD, EUR, GBP & 20+ currencies at ECB reference rates
378 conversionsFraction & Decimal
Decimals to fractions, percents & back — exact answers
199 convertersEV Running Costs
Running cost, charging cost & TCO by model
281 modelsNumber Bases
Binary, octal, decimal & hex — convert any base
207 convertersShoe Sizes
US, UK, EU & cm shoe-size charts for men & women
24 conversionsTime Formats
Military time, Unix timestamps & decimal time
102 convertersRoman Numerals
Numbers to roman numerals & back — with breakdowns
306 convertersForce
Newtons, pounds-force, kgf, dyne & poundal
20 convertersTorque
Newton-metres, lb-ft, lb-in, kgf·m & oz-in
18 convertersDoubling Time by Rate
How many years to double your money at 1%–20% — Rule of 72 vs. exact
20 rates