# 123 Calculators

> Free online calculators for loans, investments, crypto, tips, BMI, and more. Simple, fast, and accurate tools for personal finance and daily calculations.

Every tool and article on 123 Calculators is free to use — no sign-up required. The links below are the primary, canonical resources on this site.

## Tools

- [Love Calculator](https://123calculators.com/calculator/love-calculator/): Fun love compatibility calculator. Enter two names and discover your love percentage with our entertaining relationship tool.
- [Pregnancy Due Date Calculator](https://123calculators.com/calculator/pregnancy-due-date-calculator/): Calculate your pregnancy due date from last menstrual period or conception date. Track trimester milestones week by week.
- [CGPA to Percentage Calculator](https://123calculators.com/calculator/cgpa-to-percentage-calculator/): Convert CGPA to percentage and vice versa. Supports multiple university grading systems and conversion formulas.
- [Fuel Cost Calculator](https://123calculators.com/calculator/fuel-cost-calculator/): Estimate fuel costs for any trip based on distance, fuel efficiency, and current gas prices. Plan road trip budgets.
- [Electricity Bill Calculator](https://123calculators.com/calculator/electricity-bill-calculator/): Calculate your monthly electricity bill from appliance usage, wattage, and local electricity rates. Find energy-saving opportunities.
- [Crypto Profit Calculator](https://123calculators.com/calculator/crypto-profit-calculator/): Calculate crypto trading profits and losses. Enter buy and sell prices to see ROI, total gain, and tax implications.
- [Dog Age Calculator](https://123calculators.com/calculator/dog-age-calculator/): Convert your dog's age to human years using the updated scientific formula. More accurate than the old 7-year rule.
- [Grade Calculator](https://123calculators.com/calculator/grade-calculator/): Calculate your overall grade from weighted assignments, exams, and projects. See what scores you need to reach your target grade.
- [Stock Return Calculator](https://123calculators.com/calculator/stock-return-calculator/): Calculate stock investment returns including dividends, capital gains, and total ROI over your holding period.
- [Percentage Calculator](https://123calculators.com/calculator/percentage-calculator/): Calculate percentages instantly — find what % one number is of another, percentage change, X% of Y, tips, and discounts. Fast, accurate, no sign-up n…
- [Tip & Bill Splitter](https://123calculators.com/calculator/tip-and-bill-splitter/): Split your restaurant bill instantly. Enter the total, choose a tip %, and divide the cost across any number of people with exact per-person amounts.
- [BMI Calculator](https://123calculators.com/calculator/bmi-calculator/): Calculate your BMI using height and weight in metric or imperial units. Get instant WHO category results — underweight, normal, overweight, or obese.
- [Loan EMI Calculator](https://123calculators.com/calculator/loan-emi-calculator/): Free Loan EMI Calculator — enter principal, annual interest rate, and tenure in months to instantly get your monthly EMI, total interest, and total p…
- [Age Calculator](https://123calculators.com/calculator/age-calculator/): Calculate your exact age in years, months, and days from your birth date. See total days lived and countdown to your next birthday — instantly.
- [Unit Converter](https://123calculators.com/calculator/unit-converter/): Unit Converter — instantly convert length, weight, temperature, area, and volume between metric and imperial units. Live two-way conversion, no libra…
- [Compound Interest Calculator](https://123calculators.com/calculator/compound-interest-calculator/): Calculate compound interest on savings or investments. Adjust principal, rate, compounding frequency, and monthly contributions to see real growth ov…
- [Scientific Calculator](https://123calculators.com/calculator/scientific-calculator/): Free scientific calculator with trig, logs, powers, roots, factorials, hyperbolic functions, and constants. Works instantly in your browser — no inst…
- [Date Difference Calculator](https://123calculators.com/calculator/date-difference-calculator/): Calculate the exact difference between two dates in days, weeks, months, and working days. Also add or subtract durations from any date. Free, instan…
- [Fraction Calculator](https://123calculators.com/calculator/fraction-calculator/): Free fraction calculator — add, subtract, multiply, or divide fractions with automatic simplification to lowest terms and decimal conversion. Works i…
- [Discount & Sale Price Calculator](https://123calculators.com/calculator/discount-and-sale-price-calculator/): Calculate sale prices after single or stacked discounts. See final cost, total amount saved, and the real effective percentage off in seconds.
- [GPA Calculator](https://123calculators.com/calculator/gpa-calculator-2/): Free GPA calculator: enter course grades and credit hours to compute your weighted GPA on a 4.0 scale with letter-grade and percentage mapping.

## Articles

- [Dedicated Business Phone Number: 11 Reasons g100.us Wins](https://123calculators.com/dedicated-business-phone-number-g100us/): Get a dedicated business phone number in 100+ countries with g100.us. Calls, SMS & WhatsApp on one line, flat pricing, instant activation.
- [The Cheapest Reliable Business Phone Number in 2026: g100.us](https://123calculators.com/cheapest-reliable-business-phone-number-g100us/): Get a cheap business phone number that actually works. Step-by-step guide to setting up calls, SMS & WhatsApp on one line with g100.us in minutes.
- [What Calculator Usage Data Reveals About How People Handle Money](https://123calculators.com/what-calculator-data-reveals-about-money/): What calculator usage data reveals about real financial behavior — budgeting stress, late-night recalculations, and patterns in how people actually h…
- [The Psychology of Discounts: Why '50% Off' Isn't Always a Deal](https://123calculators.com/psychology-of-discounts/): Learn how retailers use anchoring, stacked discounts, and urgency to make savings feel bigger than they are — and how to calculate what you're actual…
- [Fractions Aren't Scary: A Plain-English Guide to the Four Operations](https://123calculators.com/fractions-arent-scary-guide/): Learn all four fraction operations with plain-English explanations and everyday analogies. Adding, subtracting, multiplying, and dividing made simple.
- [GPA Demystified: How Weighted Grade Averages Actually Work](https://123calculators.com/gpa-demystified-weighted-averages/): Learn how GPA is really calculated — credit-hour weighting, the 4.0 scale explained simply, and why two students with identical grades can have diffe…
- [Your Questions About Calculating Age and Date Differences, Answered](https://123calculators.com/questions-about-calculating-age-and-dates/): Confused by leap years, inclusive day counts, or working days calculators? This Q&A answers the most common date and age calculation questions clearl…
- [Metric vs Imperial: Why the World Can't Agree on Measurement](https://123calculators.com/metric-vs-imperial-measurement/): Metric vs. imperial: the history, the rivalry, and why unit conversions still trip everyone up — from NASA disasters to Canadian measurement schizoph…
- [How I Finally Stopped Awkwardly Splitting Restaurant Bills](https://123calculators.com/how-i-stopped-awkwardly-splitting-bills/): Tired of awkward restaurant bill splits? One person's honest story and a repeatable method for fair, fast splits using a bill calculator — no drama r…
- [7 Everyday Situations Where Quick Percentage Math Saves You Money](https://123calculators.com/7-everyday-situations-percentage-math-saves-money/): Discover 7 real-life situations — sales, tips, loans, salary hikes — where fast percentage math saves you money. Practical tips with actual numbers.
- [The Real Math Behind Your Loan EMI, Explained Without Jargon](https://123calculators.com/the-real-math-behind-your-loan-emi/): Understand the real EMI amortization formula, how principal vs interest shifts over a loan's life, and why prepaying early saves so much money.
- [Is BMI Actually a Useful Number? What the Science Really Says](https://123calculators.com/is-bmi-actually-useful/): Is BMI actually useful? We examine the science behind BMI's accuracy, where it breaks down for athletes and different ethnicities, and better alterna…
- [Simple vs Compound Interest: Which One Is Quietly Costing You More?](https://123calculators.com/simple-vs-compound-interest/): Simple vs compound interest compared side by side on identical loans and savings. See the real rupee difference over 5, 10, and 20 years — and which …
- [How to Calculate a Percentage by Hand (and When to Just Use a Tool)](https://123calculators.com/how-to-calculate-a-percentage-by-hand/): Learn how to calculate percentages by hand using one simple formula. Worked examples: tips, sales tax, exam grades, and discounts — plus when to use …
- [Credit Score Basics: What It Is and How to Make It Better](https://123calculators.com/credit-score-improve-fast/): If you have ever wondered why some people get better interest rates than others, the answer is usually their credit score. But what exactly is a cred…
- [What Is a High Yield Savings Account? Everything You Need to Know](https://123calculators.com/high-yield-savings-accounts-guide/): You do not need a degree in economics to manage your money well. The most important financial concepts are actually pretty simple once someone explai…
- [Pregnancy Due Date Calculator — Week by Week Guide for Expecting Mothers](https://123calculators.com/pregnancy-due-date-calculator-week-by-week-guide/): Guide to understanding your electricity bill. Learn about tariff slabs, peak hours, and practical ways to reduce energy costs.
- [Electricity Bill Calculator — How to Reduce Your Power Costs](https://123calculators.com/electricity-bill-calculator-reduce-power-costs/): Understanding CGPA grading systems worldwide. How to convert between CGPA, percentage, and letter grades accurately.
- [Cryptocurrency Profit Calculator — How to Track Your Crypto Gains](https://123calculators.com/cryptocurrency-profit-calculator-track-gains/): Complete GPA calculation guide. Learn weighted vs unweighted GPA, how to improve your GPA, and what colleges look for.
- [How to Calculate Your GPA — Complete Guide for College Students](https://123calculators.com/how-to-calculate-gpa-college-students/): Week-by-week pregnancy timeline with baby development milestones. Understanding due date calculations and what to expect.
- [Love Calculator — Does Name Compatibility Really Work? Fun Guide](https://123calculators.com/love-calculator-name-compatibility-guide/): How love calculators work and the math behind compatibility scores. A fun look at relationship algorithms and numerology.

## About & Policies

- [About Us](https://123calculators.com/about/)
- [Contact Us](https://123calculators.com/contact/)
- [Privacy Policy](https://123calculators.com/privacy-policy/)
- [Terms of Service](https://123calculators.com/terms-of-service/)
- [Disclaimer](https://123calculators.com/disclaimer/)
- [Blog](https://123calculators.com/blog/)

## Notes

- Full URL list: https://123calculators.com/sitemap.xml
- Content is original and maintained by 123 Calculators. Attribution is appreciated when cited.