Calculator Guides & Tips

June 14, 2026 How to Calculate GPA: The 4.0 Scale Explained Convert letter grades to grade points and compute your semester GPA step by step. June 13, 2026 Age on a Specific Date: How to Calculate It Exactly Find anyone's exact age on any past or future date — the method and a free tool. June 11, 2026 How to Find the LCM of Two Numbers (3 Methods) Prime factorization, listing multiples, and the GCD formula — with examples. June 9, 2026 How to Calculate Your Paycheck: Federal, FICA & State Tax Where every dollar of your paycheck goes — 2025 brackets explained. June 7, 2026 How Many Calories Does Walking Burn? (With Calculator) Calories per mile by weight and pace — plus how to burn more. June 5, 2026 Gallons to Liters: The Exact Conversion (+ Quick Chart) 1 gallon = 3.78541 liters. Chart, formula and common conversions. June 12, 2026 Best Palworld Breeding Combos for Powerful Pals The fastest breeding paths to top-tier Pals like Anubis, Jormuntide and Astegon. June 10, 2026 Pokémon IV Guide: How to Check and Maximize IVs What IVs are, how to check them, and how to breed perfect Pokémon. June 8, 2026 OSRS: Fastest 99s Ranked by Hours Which Old School RuneScape skills are fastest to 99 — and the XP math behind them. June 6, 2026 Path of Exile Currency Guide: Exchange Rates Explained How PoE's player-driven currency market works and how to convert like a pro. June 4, 2026 How to Calculate Amazon FBA Fees (Step by Step) Referral fees, FBA fulfillment fees and a worked example you can copy. June 2, 2026 eBay vs Amazon Seller Fees: Which Is Cheaper? Head-to-head fee comparison with real numbers at three price points. May 30, 2026 How to Calculate TDEE (and Actually Use It) The Mifflin-St Jeor formula, activity multipliers, and setting calorie targets. May 28, 2026 How Much House Can I Afford? The 28/36 Rule Lenders' favorite affordability rule, explained with a worked example. May 26, 2026 How to Calculate Your Monthly Mortgage Payment The amortization formula, a worked example, and what PITI adds. May 24, 2026 What Is BMI and How Is It Calculated? The BMI formula, categories, and what it doesn't tell you. May 22, 2026 How to Calculate eBay & Amazon Seller Fees The exact fee math for both marketplaces, side by side. May 20, 2026 How to Calculate How Much Concrete You Need Cubic yards, cubic feet and bag counts for slabs, footings and columns. May 18, 2026 Common Unit Conversions: The Cheat Sheet The conversions people search for most, with exact factors. May 16, 2026 How to Calculate Profit Margin (and Markup) Margin vs markup explained with formulas and a pricing example.