Disclaimer

Calculators and tools are provided for informational and educational purposes only. Always consult certified professionals for financial, medical, or legal advice.

SKMultiTools — Free Online Tools Directory

Browse our complete collection of 60+ free online calculators, converters, and utilities.

Content Tools

YouTube Title Analyzer — Optimize your YouTube titles for maximum clicks and SEO in seconds.
YouTube Description Generator — Create fully formatted YouTube descriptions with timestamps, links, and hashtags.
YouTube Tags Generator — Generate SEO-optimized tags from your video title for better discoverability.
Image Resizer — Resize images for social media, web, or custom dimensions — fully in your browser.
Image Format Converter — Convert images between JPG, PNG, and WebP — batch convert multiple files at once.
Construction Calculator — Square footage, tile count, paint gallons, and concrete volume — all home project needs.

Ai tools Tools

Hashtag Generator — Get trending hashtags for Instagram, TikTok, YouTube, Pinterest and more — 10 niches.
Instagram Bio Generator — Create catchy, stylish Instagram bios across 4 styles — creator, business, personal.
AI Prompt Optimizer — Perfect prompts for ChatGPT, Gemini, Claude, Midjourney, and DALL·E 3.
Thumbnail Clickbait Score — Analyze 10 key factors and score your YouTube thumbnail's click-through potential.
Content Repurposing Calculator — Plan how to repurpose one video across 10+ platforms with time and reach estimates.
Video Editing Time Estimator — Predict realistic editing time by video type, complexity, and experience level.
Character Limit Checker — Check your text against 20 platform limits — Twitter, Instagram, Meta ads, YouTube, SMS.
Creator Earnings Calculator — Estimate income from YouTube, TikTok, Instagram, AdSense, and freelancing.

Finance Tools

Loan EMI Calculator — Calculate monthly loan installments for car, home, and personal loans with amortization.
SIP & Lumpsum Calculator — Estimate future value of systematic investments or one-off deposits with projections.
Compound Interest Calculator — See how compounding grows your savings faster — with year-by-year breakdown.
Inflation Adjuster — See how inflation erodes purchasing power over time — with year-by-year breakdown.
Income Tax Estimator — India FY2024-25 tax estimate — New vs Old regime comparison with slab breakdown.
Age Calculator — Check your exact age in years, months, days — and upcoming birthday countdown.
Percentage Calculator — 5 modes: % of number, what percent, percent change, increase/decrease, tip calculator.
GPA / CGPA Calculator — Calculate semester & cumulative GPA on a 4.0 or 10-point scale with full grade table.
Mortgage Calculator — Monthly payment, total interest, amortization schedule, and extra payment savings.
Fuel Cost & Mileage Calculator — Trip fuel cost, mileage, annual spend, and vehicle comparison — gas, diesel, or electric.
Salary Calculator — Salary ↔ hourly conversion, overtime pay, and pay raise calculator — all in one.
Business Calculator — Profit margin, break-even analysis, ROI, and flat or tiered commission calculator.
Tax & Discount Calculator — Add/extract VAT, sales tax, flat discounts, and combined discount+tax pricing.
Debt Payoff Calculator — Snowball vs avalanche method — find the fastest, cheapest path to debt freedom.
Currency Exchange Calculator — Convert between 27 world currencies — quick pairs, common amounts, and all-currency view.

Health Tools

BMI Calculator (Men & Women) — BMI with visual gauge, BMR, TDEE, body fat estimate, calorie goals, and WHO classification.
Calorie Deficit Calculator — Calculate BMR and TDEE with Mifflin-St Jeor — 5 activity levels, weight and deficit goals.
Water Intake Calculator — See how much water you should drink based on weight, activity, and climate.
Ideal Weight Calculator — Estimate ideal weight using 4 medical formulas — Devine, Robinson, Miller, Hamwi.
Sleep Calculator — Find optimal bed & wake times based on 90-minute REM cycles, plus nap recommendations.
Macro Nutrient Calculator — Daily protein, carb, and fat targets for your body stats and goal — with food reference.
Body Fat Percentage Calculator — US Navy + BMI methods — fat mass, lean mass, and ideal body fat targets.
Pregnancy Due Date Calculator — Due date by LMP or conception date + ovulation window and 3-cycle fertile period forecast.
Age Difference Calculator — Find the exact age gap between two people — years, months, days, weeks, hours.

Science/math Tools

Unit Converter — Convert units for length, mass, temperature, speed, volume, and more.
Trigonometric Solver — Sin, cos, tan, inverse & hyperbolic functions + triangle solver (Law of Sines).
Matrix Calculator — Add, subtract, multiply, transpose, determinant & inverse — 2×2 and 3×3 matrices.
Physics Equation Calculator — Solve any variable in 12 physics equations — mechanics, electricity, waves.
Number Base Converter — Binary, Octal, Decimal, Hex & any base 2-36. Also a full binary & hexadecimal calculator.
Statistics Calculator — Mean, median, mode, std dev, quartiles, IQR, skewness, histogram — from any dataset.
Fraction Calculator — Add, subtract, multiply, divide fractions with automatic simplification and decimal/% output.

Coding Tools

JSON Formatter — Format, minify, validate JSON and convert to YAML — with depth, key count, and size stats.
Base64 Encoder/Decoder — Encode or decode data as Base64 — strings, files, or raw binary.
String Case Converter — Switch between camelCase, PascalCase, UPPER, lower, title, snake_case, kebab-case.
Lorem Ipsum Generator — Generate placeholder text for wireframes, mockups, and layouts — paragraphs or words.
Regex Tester & Builder — Live match highlighting, capture groups, replace, 16-pattern library — full regex toolkit.
Word Counter & Analyzer — Words, chars, readability score, keyword density, top keywords, and sentence stats.
Color Converter — Convert HEX ↔ RGB ↔ HSL, WCAG contrast ratios, shade generator, and color palette.
Password Generator — Generate cryptographically secure passwords with strength meter and entropy analysis.
URL Encoder / Decoder — Encode, decode URLs and query strings — plus a full query parameter parser.
Text Diff Checker — Compare two texts and highlight differences line-by-line or word-by-word.
Markdown Preview — Live Markdown editor with rendered preview, HTML export, and writing statistics.
Scientific Calculator Online — Full scientific calculator — trig, log, power, factorial, keyboard support, history.
Time Zone Converter — Live clocks + custom time conversion across 23 world time zones.
Date Countdown Calculator — Live countdown to any event — days, hours, minutes, seconds. Add multiple events.
Time Duration Calculator — Calculate exact duration between two times or dates — hours, minutes, seconds, days.