Blog
Guides, tips and tutorials for our free online tools.
TDEE Calculator — How Many Calories Do You Burn Per Day?
Learn how to calculate your Total Daily Energy Expenditure using the Mifflin-St Jeor equation. Free TDEE calculator with activity levels.
Macro Calculator — How to Calculate Your Macros Free
Calculate your ideal daily protein, carbs and fat intake based on calories and fitness goals. Free online macro calculator tool.
Body Fat Percentage: How the US Navy Method Works and How to Measure
Estimate your body fat percentage using the US Navy method from simple body measurements. See fat mass, lean mass and category.
Calorie Deficit 101: The Science of Safe, Sustainable Weight Loss
Calculate the daily calorie deficit needed to reach your weight loss goal safely. Get a timeline and daily calorie target. Free tool.
What Should You Weigh? Four Formulas, One Honest Answer
Calculate your ideal body weight using Devine, Robinson, Miller and Hamwi formulas. See your healthy weight range by height and gender.
Sleep Cycles Explained: Why Timing Matters More Than Duration
Calculate optimal bedtime and wake-up times based on 90-minute sleep cycles. Wake up refreshed instead of groggy. Free sleep tool.
Water Intake Calculator — How Much Water Per Day Free
Calculate your daily water intake based on weight, activity level and climate. Get personalized hydration targets. Free online tool.
Protein Calculator — How Much Protein Do You Need Free
Calculate your optimal daily protein intake based on body weight, activity and goals. See per-meal targets. Free protein intake calculator.
Heart Rate Training Zones: How to Use Them for Better Workouts
Calculate your 5 heart rate training zones using the Karvonen method. Find fat burn, cardio and peak zones from age and resting HR.
One Rep Max: How to Estimate Your Strength Without Testing It
Calculate your one-rep max from any weight and rep count using Epley, Brzycki and Lombardi formulas. Free online 1RM calculator.
Blood Alcohol Content: What BAC Means and How Drinks Add Up
Estimate your blood alcohol content based on drinks consumed, weight, gender and time. Uses the Widmark formula. Free BAC calculator.
Pace Calculator — Running Pace, Speed & Race Time Free
Calculate running pace in min/km or min/mile, speed, and finish times for 5K, 10K, half marathon and marathon. Free pace calculator.
Pregnancy Due Date Calculator — Estimate Delivery Date Free
Calculate your estimated due date from last menstrual period or conception date. See trimester, current week and progress. Free tool.
VO2 Max: The Single Best Measure of Your Cardiovascular Fitness
Estimate your VO2 max from the Cooper 12-minute run test or Rockport walk test. See your fitness category by age and gender. Free tool.
QR Code Generator — Create QR Codes Online Free
Generate QR codes from text, URLs, WiFi credentials and more. Download as PNG or SVG. Free online QR code generator with custom colors.
Generate Secure Passwords Online — Free Password Generator
Create strong, random passwords with custom length and character options. Free online password generator — nothing stored, fully private.
How to Format JSON Online — Free JSON Formatter & Validator
Format, validate and prettify JSON data online for free. Paste messy JSON and get clean, indented output in one click.
Word Counter: How to Check Word Count, Characters and Reading Time
Count words, characters, sentences and lines in any text instantly. Free online word counter with reading time estimate.
What Is Base64? A Developer's Guide to Encoding and Decoding
Encode and decode Base64 strings instantly. Learn what Base64 is, when to use it, and convert data in your browser for free.
UUID Generator: What UUIDs Are and How to Create Them Instantly
Generate random UUID v4 identifiers instantly. Learn what UUIDs are, when to use them, and create as many as you need for free.
Regular Expressions Demystified: Test and Debug Regex Patterns
Test and debug regular expressions in real time with match highlighting. Free online regex tester with explanation and cheat sheet.
HEX vs RGB vs HSL: Which Color Format Should You Use?
Convert colors between HEX, RGB, and HSL formats instantly. Free online color converter for web developers and designers.
Unix Timestamp Converter — Epoch Time to Date Online
Convert Unix timestamps to human-readable dates and back. Supports seconds and milliseconds. Free online epoch converter.
Lorem Ipsum: Why Designers Still Use 500-Year-Old Placeholder Text
Generate Lorem Ipsum placeholder text for designs and layouts. Choose paragraphs, sentences, or words. Free instant dummy text.
Markdown Preview Online — Free Live Markdown Renderer
Write Markdown and see it rendered as HTML in real time. Free online Markdown preview tool for README files, docs, and blog posts.
Percent-Encoding Explained: When and How to Encode URLs
Encode or decode URLs and query strings online for free. Learn how percent-encoding works and fix broken links instantly.
HTML Entities Explained: Encode Special Characters Safely
Encode or decode HTML entities instantly. Convert special characters like angle brackets and ampersands for safe HTML embedding.
JWT Decoder — Inspect JSON Web Tokens Online Free
Decode and inspect JWT tokens instantly. View header, payload, and signature. Free online JWT decoder — no data sent to any server.
SHA Checksums: How to Verify File Integrity with Hash Functions
Calculate SHA-1, SHA-256, SHA-384 and SHA-512 checksums for any text online. Free browser-based hash generator — no data uploaded.
JavaScript & CSS Minifier — Minify Code Online Free
Minify JavaScript and CSS code online in seconds. Remove whitespace, comments and reduce file size. Free browser-based minifier.
Cron Jobs Explained: Build Cron Expressions Without Memorizing Syntax
Build and understand cron expressions with a visual editor. See next run times and human-readable descriptions. Free cron builder.
SQL Formatter — Prettify SQL Queries Online Free
Format and beautify SQL queries with proper indentation and keyword capitalization. Free online SQL formatter for any dialect.
XML Formatting: How to Read, Validate and Debug XML Documents
Format, indent and validate XML documents online. Turn minified XML into readable structured output. Free XML prettifier tool.
YAML vs JSON: Differences, Conversion and When to Use Each
Convert between YAML and JSON formats instantly. Validate YAML syntax and transform to JSON for API use. Free online converter.
JSON to CSV Converter — Transform JSON Data Online Free
Convert JSON arrays to CSV format instantly. Handles nested objects and arrays. Free online JSON to CSV converter — no upload needed.
HTML to Markdown: How to Convert Web Content for Static Sites
Convert HTML to clean Markdown instantly. Handles headings, links, images, lists and tables. Free online HTML to Markdown tool.
Text Diff Checker — Compare Two Texts Online Free
Compare two blocks of text and see the differences highlighted. Free online diff checker with line-by-line and word-by-word modes.
camelCase, snake_case, UPPER_CASE: Convert Between Naming Conventions
Convert text between uppercase, lowercase, title case, sentence case, camelCase and more. Free instant case converter online.
Code Screenshot Generator — Beautiful Code Images Free
Create beautiful screenshots of your code with syntax highlighting and custom themes. Free online code-to-image tool for social media.
Timezone Converter — Convert Times Between Zones Free
Convert times between any world timezones instantly. Plan meetings across time zones with our free online timezone converter tool.
Binary, Hex, Octal and Decimal: How Number Bases Work
Convert numbers between binary, octal, decimal and hexadecimal bases instantly. Free online number base converter for developers.
Color Palette Generator — Create Color Schemes Online Free
Generate harmonious color palettes for your designs. Explore complementary, analogous and triadic schemes. Free online palette tool.
CSS Gradient Generator — Create Gradients Online Free
Build beautiful CSS gradients with live preview. Linear, radial, and conic gradients with custom colors and angles. Free gradient tool.
CSS Box Shadow Generator — Visual Shadow Builder Free
Create CSS box shadows with a visual editor. Adjust offset, blur, spread and color in real time. Free online box shadow generator.
WCAG Contrast Ratios Explained: How to Check Your Colors Pass AA
Check color contrast ratios against WCAG AA and AAA standards. Ensure your text is readable for all users. Free accessibility tool.
Flexbox Generator — Visual CSS Flexbox Builder Free
Build CSS Flexbox layouts visually. Experiment with flex direction, alignment, wrapping and gaps. Free online Flexbox generator tool.
CSS Grid Generator — Visual Grid Layout Builder Free
Build CSS Grid layouts visually. Define rows, columns, gaps and areas with live preview. Free online CSS Grid generator tool.
Typography Scales: Why Your Font Sizes Should Follow a Ratio
Generate a modular typography scale with perfect font size ratios. Get CSS-ready type scale for your design system. Free online tool.
Font Pairing: Rules for Combining Typefaces That Actually Work
Discover beautiful Google Font pairings for your website. See live previews of heading and body font combinations. Free pairing tool.
Aspect Ratio Calculator — Calculate Dimensions Online Free
Calculate width and height for any aspect ratio. Resize images and videos proportionally. Free online aspect ratio calculator tool.
Favicon Generator — Create Favicons from Text or Emoji Free
Generate favicon.ico files from text, letters or emoji. Create browser tab icons in all required sizes. Free online favicon maker.
Image Color Extractor — Pick Colors from Any Image Free
Extract the dominant color palette from any image. Get HEX, RGB and HSL codes for each color. Free online image color picker tool.
CSS @keyframes: Build Smooth Animations Without JavaScript
Create CSS keyframe animations visually. Build bounce, fade, slide and custom animations with live preview. Free animation generator.
Designing for Color Blindness: How 8% of Men See Your UI
Simulate how your colors appear to people with color blindness. Test for protanopia, deuteranopia, tritanopia and more. Free tool.
Tints & Shades Generator — Create Color Variations Free
Generate lighter tints and darker shades from any base color. Build complete color scales for design systems. Free online tool.
Line Height Calculator — Optimal Line Spacing Online Free
Calculate the perfect line height for any font size. Get optimal line spacing and letter spacing for maximum readability. Free tool.
Spacing Scale Generator — Consistent Spacing System Free
Generate a consistent spacing scale for margins and padding. Build design system spacing tokens with our free online generator.
SVG Viewer & Optimizer — Preview & Minify SVG Free
Preview SVG code instantly and optimize file size by removing unnecessary data. Free online SVG viewer and optimizer tool.
Placeholder Image Generator — Custom Dummy Images Free
Generate placeholder images at any size and color. Perfect for mockups and development. Free online placeholder image generator tool.
CSS Clip-Path: How to Create Non-Rectangular Shapes in CSS
Build CSS clip-path shapes visually. Create polygons, circles, and custom clipping paths with live preview. Free online generator.
Blob Generator — Create SVG Blob Shapes Online Free
Generate organic blob shapes as SVG for backgrounds and decorations. Customize complexity and color. Free online blob maker tool.
Border Radius Generator — CSS Rounded Corners Online Free
Create complex CSS border-radius values visually. Generate pill shapes, organic corners and asymmetric radii. Free online tool.
Glassmorphism in CSS: The Frosted Glass Effect Explained
Create glassmorphism CSS effects with frosted glass, blur and transparency. Live preview with customizable settings. Free online tool.
CSS Loader Generator — Animated Spinners & Loaders Free
Create pure CSS loading spinners and animations. Choose from dozens of styles and customize colors and size. Free loader generator.
CSS Text Shadow Generator — Text Effects Online Free
Create CSS text-shadow effects visually. Build glow, emboss, 3D and outline text effects. Free online text shadow generator tool.
BMI Calculator — Body Mass Index Calculator Free
Calculate your Body Mass Index (BMI) with height and weight. See your BMI category and health interpretation. Free online BMI tool.
Percentage Calculator — Percent, Increase & Decrease Free
Calculate percentages, percentage increase, decrease and difference. Solve any percentage problem instantly. Free online calculator.
Age Calculator — Calculate Exact Age from Birthday Free
Calculate your exact age in years, months and days from any birthdate. Find days until next birthday. Free online age calculator.
Unit Converter — Length, Weight, Temperature & More Free
Convert between units of length, weight, temperature, volume, speed and more. All-in-one free online unit converter tool.
Loan Calculator — Monthly Payment & Interest Free
Calculate monthly loan payments, total interest paid and amortization schedule. Works for any loan type. Free online loan calculator.
Mortgage Calculator — Monthly Payment & Amortization Free
Calculate mortgage payments with principal, interest, taxes and insurance. See full amortization schedule. Free online mortgage tool.
How GPA Is Calculated: A Student's Guide to Grade Point Average
Calculate your GPA from letter grades and credit hours. Supports 4.0, 4.3, and weighted scales. Free online GPA calculator tool.
Tip Calculator & Bill Splitter — Calculate Tips Free
Calculate tips and split bills easily among any number of people. Choose custom tip percentages. Free online tip calculator tool.
Compound Interest: How $500/Month Becomes $1 Million
Calculate compound interest and see how your investments grow over time. Visualize returns with charts. Free online compound interest tool.
Discount Calculator — Sale Price & Savings Calculator Free
Calculate sale prices and savings from any discount percentage. See how much you save instantly. Free online discount calculator.
Salary Calculator — Hourly, Weekly & Annual Conversion Free
Convert salary between hourly, weekly, biweekly, monthly and annual amounts. Compare job offers easily. Free online salary calculator.
Date Calculator — Days Between Dates & Date Math Free
Calculate the number of days between two dates or add/subtract days from a date. Free online date difference calculator tool.
Road Trip Fuel Costs: How to Budget Gas for Any Drive
Estimate fuel costs for any trip. Enter distance, fuel economy and gas price to calculate total cost. Free online fuel calculator.
What Does It Cost to Run That Appliance? Calculate Electricity Usage
Calculate electricity costs for any appliance. Enter wattage, usage hours and rate to see daily, monthly and annual costs. Free tool.
ROI Explained: How to Calculate Return on Any Investment
Calculate return on investment (ROI) percentage and annualized returns. Compare investment performance easily. Free online ROI tool.