Free Online Calculators — Finance, Marketing, Tax & Fuel
Stop guessing. Start measuring. CalcFuel gives you instant answers on ROI, ROAS, email metrics, social media performance, and more — all free, no sign-up required.
✉️ Email Marketing
View all →Email Open Rate Calculator
Calculate your email open rate from opens and deliveries.
Try it free →Email List Growth Rate Calculator
Track net subscriber growth as a percentage of your list size.
Try it free →Click-Through Rate Calculator
Calculate CTR for ads, emails, and organic search listings.
Try it free →💰 Financial & ROI
View all →Marketing ROI Calculator
Measure the return on your marketing investment.
Try it free →ROAS Calculator
Calculate your Return on Ad Spend instantly.
Try it free →Ad Spend Calculator
Plan your ad budget: clicks, leads, revenue, and ROI.
Try it free →Customer Acquisition Cost Calculator
Calculate how much you spend to acquire each new customer.
Try it free →Customer Lifetime Value Calculator
Measure the total revenue value of each customer relationship.
Try it free →Marketing Budget Calculator
Get a recommended marketing budget based on revenue and industry.
Try it free →Australian Income Tax Calculator
Calculate income tax, Medicare levy, LITO, and take-home pay for 2025-26.
Try it free →GST Calculator
Add or remove GST from any Australian price. Standard 10% rate.
Try it free →Profit Margin Calculator
Calculate gross, net, and operating profit margins instantly.
Try it free →Break-Even Calculator
Find the sales volume needed to cover your fixed costs.
Try it free →Average Order Value Calculator
Track your average transaction size over any period.
Try it free →📱 Social Media
View all →Social Media ROI Calculator
Measure the ROI of your social media ad spend.
Try it free →Social Media Engagement Rate Calculator
Calculate engagement rate for Instagram, LinkedIn, TikTok, and more.
Try it free →Follower Growth Rate Calculator
Track your social media audience growth rate over any period.
Try it free →Social Media Character Counter
Live character count for Twitter/X, LinkedIn, Instagram, and Facebook.
Try it free →Post Length Optimizer
Get optimal length recommendations for every social platform.
Try it free →🎯 Conversion & Leads
View all →Conversion Rate Calculator
Measure how effectively your pages turn visitors into customers.
Try it free →Cost Per Lead Calculator
Calculate your cost per lead and compare across channels.
Try it free →Cost Per Acquisition Calculator
Calculate your cost to acquire a paying customer.
Try it free →Revenue Per Lead Calculator
Find the revenue value of each marketing lead generated.
Try it free →Churn Rate Calculator
Measure how many customers you lose each period.
Try it free →🔍 SEO Tools
View all →Website Speed Impact Calculator
See how faster load times increase conversions and revenue.
Try it free →Website Traffic Calculator
Project organic traffic growth from SEO improvements.
Try it free →Net Promoter Score Calculator
Calculate your NPS from promoter and detractor responses.
Try it free →Marketing Health Check
10-question quiz: score your marketing foundation and get recommendations.
Try it free →🤖 AI Developer Tools
View all →AI Model Router Savings Calculator
See how much you save routing easy queries to cheaper models.
Try it free →Prompt Caching Discount Estimator
Calculate exact savings from caching system prompts with Claude, GPT-4o, or Gemini.
Try it free →Multimodal Payload Estimator
Estimate token counts and costs for images, video, and audio across GPT-4o, Claude, and Gemini.
Try it free →⛽ Fuel & Energy
View all →Trip Fuel Cost Calculator
Calculate total fuel cost for any road trip.
Try it free →Commute Fuel Cost Calculator
See your daily, weekly, and annual commute fuel costs.
Try it free →Towing Fuel Cost Calculator
Calculate caravan and trailer fuel penalty for towing trips.
Try it free →EV vs Gas Calculator
Compare 5-year or 10-year total cost of ownership.
Try it free →Hybrid vs Petrol Calculator
Compare running costs between hybrid and petrol vehicles.
Try it free →Hydrogen vs Petrol Calculator
Compare hydrogen and petrol fuel costs side by side.
Try it free →Drive vs Fly Calculator
Compare the true cost of driving versus flying.
Try it free →Boat Fuel Calculator
Estimate marine fuel costs for any boat trip.
Try it free →Carpool Fuel Split Calculator
Split fuel costs fairly among passengers.
Try it free →Fuel Budget Planner
Plan your monthly fuel spend and stay on budget.
Try it free →Fuel Economy Savings Calculator
Quantify savings from improving your driving habits and MPG.
Try it free →Generator Fuel Calculator
Calculate generator runtime and fuel needed for outages.
Try it free →Fuel Surcharge Calculator
Calculate delivery fuel surcharges for freight and shipping.
Try it free →Idling Fuel Waste Calculator
See how much fuel and money you waste idling your engine.
Try it free →Emergency Fuel Rationing Calculator
Plan your fuel supply during shortages or emergencies.
Try it free →IFTA Fuel Tax Calculator
Calculate interstate fuel tax for commercial trucking.
Try it free →🇦🇺 Australian Tax & Super
View all →Income Tax Calculator
Calculate Australian income tax for 2025–26.
Try it free →Capital Gains Tax Calculator
Calculate CGT on shares, property, and crypto for 2025–26.
Try it free →Tax Refund Estimator
Estimate your Australian tax refund for 2025–26.
Try it free →Stamp Duty Calculator
Calculate stamp duty across all Australian states.
Try it free →Superannuation Calculator
Project your super balance at retirement.
Try it free →Salary Sacrifice Calculator
See how salary sacrifice boosts your super and cuts tax.
Try it free →Franking Credits Calculator
Calculate franking credits and refunds on Australian dividends.
Try it free →Negative Gearing Calculator
Model negative gearing tax benefits on investment property.
Try it free →HECS-HELP Repayment Calculator
Calculate your HECS-HELP repayments based on income.
Try it free →Work From Home Tax Calculator
Calculate WFH tax deductions for 2025–26.
Try it free →Mortgage Repayment Calculator
Calculate monthly, fortnightly, and weekly repayments.
Try it free →Loan Repayment Calculator
Calculate monthly payments and total interest on any loan.
Try it free →Compound Interest Calculator
Project savings and investment growth with compound interest.
Try it free →🧮 Everyday Tools
View all →Percentage Calculator
Fast, free percentage calculations for any use case.
Try it free →BMI Calculator
Calculate your Body Mass Index using Australian health standards.
Try it free →Age Calculator
Calculate exact age in years, months, and days.
Try it free →Tip Calculator
Split bills and calculate tips instantly.
Try it free →Get 10 free AI marketing prompts
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Real-world L/100km for 6 popular tow vehicles, costs for 5 major AU road trips, and fuel-saving tips.
Read article →Fuel & EnergyUnderstanding Fuel Economy: MPG vs L/100km Explained
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Read article →Fuel & EnergyHow to Reduce Your Commute Fuel Costs: 7 Proven Tips
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