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Evan Miller

I'm a software engineer who builds web applications and data tools. I personally implement and verify the formula and logic behind every calculator on Launch Hub. I publish them as free online tools so anyone can get an answer without signing up or paying.

Bicycle vs Car Emissions Calculator

Compare the carbon footprint of cycling versus driving for your regular trips. This tool helps eco-conscious commuters, sustainability researchers, and policy advocates quantify emission savings from choosing a bicycle over a car. Get clear breakdowns of annual and per-trip emission…

Language Learning Hour Planner

Helps students, teachers, and academic advisors plan weekly language study hours. Aligns study time with course credit requirements and CEFR proficiency goals. Tracks progress against common language learning benchmarks.

Cloth Diaper Washing Frequency Calculator

This tool helps parents and caregivers estimate how often to wash cloth diapers based on daily usage and laundry habits. It simplifies planning for busy households managing reusable diaper routines. Adjust inputs to match your family’s specific needs.

Tax Loss Harvesting Estimator

This tool helps individual investors estimate potential tax savings from selling underperforming investments to offset capital gains. It’s designed for personal budget managers, financial planners, and anyone handling taxable investment accounts. Use it to plan year-end tax strategies without complex…

Factoring Calculator

This factoring calculator helps small business owners and e-commerce sellers estimate invoice factoring costs. It breaks down advance amounts, fees, and net payouts for trade finance decisions. Use it to compare factoring terms before committing to a financing agreement.

IELTS Band Score Calculator

This tool calculates your overall IELTS band score from individual section results. It helps students, teachers, and academic advisors track academic performance and plan study goals. Use it to estimate your final score before official results are released.

Hanging Plant Weight Calculator

Estimate the total weight of your hanging plant setup to avoid damaging hooks or ceilings. This tool helps home gardeners and plant owners plan safe, sturdy displays for indoor or outdoor greenery. Use it to check if your existing hardware…

Net Lease vs Gross Lease Comparison Calculator

Compare net and gross lease costs to make informed rental decisions. This tool helps tenants, landlords, and financial planners evaluate total lease expenses across both structures. Use it to budget for occupancy costs and negotiate favorable lease terms.

Elderflower Cordial Ratio Calculator

This tool helps home cooks calculate precise ingredient ratios for elderflower cordial. Adjust batch sizes, sweetness levels, and dilution ratios to match your taste and serving needs. Perfect for small batches or large gatherings.