Free Online Tools

Calculators, converters, and dev utilities. Fast, free, no signup.

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Finance

Car Loan Calculator

Calculate your monthly car payment, total interest, and see a full amortization schedule. Enter vehicle price, down payment, interest rate, and loan term.

💰 Finance

Compound Interest Calculator

Calculate how your investments grow over time with compound interest. See total balance, earnings breakdown, and a visual growth chart.

💰 Finance

Debt Snowball vs Avalanche Calculator

Compare two debt payoff strategies side by side — see which method saves more money and gets you debt-free faster

💰 Finance

FIRE Calculator

Calculate when you can retire early — enter savings, income, and expenses to see your FIRE number, years to financial independence, and portfolio growth chart

💰 Finance

Rent Split Calculator

Split rent fairly among roommates based on room size and amenities. Add bonuses for private bathroom, balcony, windows — share the result in one click.

⚡

Dev

⚡ Dev

Aspect Ratio Calculator

Calculate width or height for any aspect ratio, or find the ratio of your image. Presets for 16:9, 4:3, 21:9, 1:1, and more.

⚡ Dev

Chmod Calculator

Calculate Linux file permissions in numeric (octal) and symbolic notation

⚡ Dev

Cron Expression Generator

Build and explain cron expressions visually. Generate cron schedules and see human-readable descriptions.

⚡ Dev

DPI / PPI Calculator

Convert pixels to print size or calculate required resolution. Enter image dimensions and DPI to get print size in inches/cm, or specify print size to find needed pixels.

⚡ Dev

.gitignore Generator

Generate .gitignore files by combining templates for languages, frameworks, IDEs, and operating systems

⚡ Dev

.gitignore for Node.js

Ready-to-use .gitignore for Node.js projects — npm, yarn, pnpm, build artifacts, and environment files

⚡ Dev

.gitignore for Python

Ready-to-use .gitignore for Python projects — virtualenv, __pycache__, pip, pytest, Jupyter, and IDE files

⚡ Dev

.gitignore for React

Ready-to-use .gitignore for React projects — CRA, Next.js, Vite, build output, node_modules, and environment files

⚡ Dev

Htaccess Redirect Generator

Generate .htaccess redirect rules — 301, 302, HTTPS, www, and canonical redirects

⚡ Dev

IP Subnet Calculator

Calculate subnet mask, CIDR notation, IP range, number of hosts, and network details from any IP address

⚡ Dev

PPI Calculator

Calculate pixel density (PPI) from screen size and resolution. Compare two displays side by side — monitors, phones, tablets, TVs.

⚡ Dev

Robots.txt Generator

Generate robots.txt files with visual editor. Block bots, set crawl rules, add sitemaps — with templates for common setups.

⚡ Dev

Text Case Converter

Convert text between camelCase, snake_case, kebab-case, PascalCase, UPPER_CASE, Title Case, and more

⚡ Dev

Text to camelCase Converter

Convert any text, snake_case, kebab-case, or PascalCase to camelCase instantly

⚡ Dev

Text to kebab-case Converter

Convert any text, camelCase, or snake_case to kebab-case instantly

⚡ Dev

Text to PascalCase Converter

Convert any text, camelCase, snake_case, or kebab-case to PascalCase instantly

⚡ Dev

Text to Slug Converter

Convert any title or text into a clean, SEO-friendly URL slug — with transliteration, stop-word removal, and custom separators

⚡ Dev

Text to snake_case Converter

Convert any text, camelCase, PascalCase, or kebab-case to snake_case instantly

⚡ Dev

TSConfig Generator

Generate tsconfig.json for any TypeScript project. Presets for Node 18/20/22, Next.js, React, libraries — with every compiler option explained.

🔧

Everyday

🔧 Everyday

Aquarium Volume Calculator

Calculate aquarium volume in liters and gallons from dimensions. Get fish stocking recommendations based on the 1 inch per gallon rule and tank shape.

🔧 Everyday

Butter Converter

Convert butter between sticks, cups, tablespoons, grams, ounces, and more — with a visual stick reference

🔧 Everyday

Fuel Cost Calculator

Calculate trip fuel cost from distance, fuel consumption, and gas price — with round-trip, carpool split, and multi-stop support

🔧 Everyday

Fuel Economy Calculator

Calculate your car's fuel consumption — enter distance driven and fuel used, get L/100km or MPG with cost per kilometer/mile

🔧 Everyday

Horsepower to kW Converter

Convert between horsepower (HP/PS/CV) and kilowatts instantly. Supports mechanical HP, metric PS, and electric motor kW. Essential for comparing car specs worldwide.

🔧 Everyday

Knitting Gauge Calculator

Calculate how many stitches to cast on based on your gauge swatch. Enter stitches per 10cm or 4 inches and desired width to get exact stitch count.

🔧 Everyday

MPG to L/100km Converter

Convert fuel economy between MPG (US/UK) and L/100km instantly. Includes km/L and mi/gal reference. The essential tool for comparing cars across regions.

🔧 Everyday

Sugar Substitute Converter

Replace sugar with honey, stevia, erythritol, or 10+ other sweeteners — with adjusted amounts, liquid changes, and baking tips

🔧 Everyday

Triangle Calculator

Enter any 3 values (sides and angles) and get everything — all sides, angles, area, perimeter, heights, and a visual diagram

🔧 Everyday

Yarn Weight Converter

Convert yarn between yards per pound, meters per 100g, and grams per meter — auto-detect yarn weight category and calculate skeins needed for your project

🏗️

Construction & DIY

🏗️ Construction & DIY

Board Foot Calculator

Calculate board feet for lumber purchases — with common size presets, nominal vs actual dimensions, project list, and price estimation

🏗️ Construction & DIY

Brick Calculator

Calculate how many bricks and how much mortar you need for a wall — with brick size presets, mortar joint thickness, openings, and waste factor

🏗️ Construction & DIY

Concrete Calculator

Calculate how much concrete you need for slabs, footings, columns, posts, and stairs — with bag estimates and waste factor

🏗️ Construction & DIY

Cubic Yard Calculator

Calculate cubic yards for any project — enter dimensions for one or multiple zones, choose a material for weight estimates, and get total volume with cost

🏗️ Construction & DIY

Drywall Calculator

Calculate how many drywall sheets you need — plus screws, joint compound, and tape estimates

🏗️ Construction & DIY

Gravel Calculator

Calculate how much gravel you need for driveways, patios, walkways, and landscaping — with weight estimates by gravel type and bag counts

🏗️ Construction & DIY

Lawn Area Calculator

Calculate lawn area for any shape — rectangle, circle, triangle, L-shape, or custom. Get seed and sod estimates for your yard size.

🏗️ Construction & DIY

Mulch Calculator

Calculate how much mulch you need for garden beds, tree rings, and pathways — with bag estimates by mulch type and coverage area

🏗️ Construction & DIY

Paint Calculator

Calculate how much paint you need for walls and ceilings — with door and window exclusions, number of coats, and coverage rate

🏗️ Construction & DIY

Roof Pitch Calculator

Calculate roof pitch from rise and run — get angle in degrees, slope percentage, and ratio (e.g. 4:12)

🏗️ Construction & DIY

Sand Calculator

Calculate how much sand you need for sandboxes, paver bases, leveling, and masonry — with weight in tons and bag estimates

🏗️ Construction & DIY

Tile Calculator

Calculate how many tiles you need for floors or walls — with pattern waste, grout gaps, box rounding, and cost estimate

🔌

Electrical

🔌 Electrical

Battery Life Calculator

Calculate how long a battery will last — enter mAh capacity and current draw, get runtime in hours and days with efficiency and discharge depth

🔌 Electrical

Electricity Cost Calculator

Calculate how much it costs to run any appliance. Add multiple devices, set your electricity rate, and see daily, monthly, and yearly costs instantly.

🔌 Electrical

LED Resistor Calculator

Calculate the resistor value for any LED — with standard E12/E24 rounding, color bands, power rating, and series LED support

🔌 Electrical

Ohm's Law Calculator

Enter any two of Voltage, Current, Resistance, and Power — instantly get the other two. The essential electrical formula tool.

🔌 Electrical

Resistor Color Code Calculator

Decode resistor color bands to value or find the right colors for any resistance — supports 4-band and 5-band resistors

🔌 Electrical

Voltage Divider Calculator

Calculate output voltage from R1 and R2, or find the right resistor pair for a desired output — with schematic diagram and E24 suggestions

🔌 Electrical

Wire Gauge Calculator

Find the right wire size for any circuit — enter amps, distance, and voltage to get AWG/mm² with voltage drop analysis

🍳

Cooking

🍳 Cooking

Cooking Temperature Converter

Convert between Fahrenheit, Celsius, Gas Mark, and Fan Oven temperatures instantly. Includes recipe-rounded values, cooking presets, and a full Gas Mark reference table.

🍳 Cooking

Cups of Butter to Grams

Convert cups of butter to grams and back. Includes stick-to-gram conversions, tablespoon equivalents, and common baking amounts.

🍳 Cooking

Cups of Flour to Grams

Convert cups of flour to grams instantly. Covers all-purpose, bread, cake, whole wheat, almond, and coconut flour with accurate weights.

🍳 Cooking

Cups of Oats to Grams

Convert cups of oats to grams — rolled oats, quick oats, and oatmeal. Accurate weights for baking, overnight oats, and meal prep.

🍳 Cooking

Cups of Rice to Grams

Convert cups of rice to grams — white, brown, basmati, jasmine. Get accurate weights for uncooked rice with portion planning tips.

🍳 Cooking

Cups of Sugar to Grams

Convert cups of sugar to grams — granulated, brown, powdered, honey, and maple syrup. Accurate weights for every type.

🍳 Cooking

Cups to Grams Converter

Convert cups to grams for 40+ baking ingredients. Select flour, sugar, butter, rice, oats, or any ingredient — get accurate gram weights instantly.

🍳 Cooking

Meat Roasting Calculator

Enter meat type, weight, and doneness — get oven temperature, total roasting time, and resting time. Works for beef, pork, chicken, turkey, and lamb.

🍳 Cooking

Pasta Portion Calculator

How much pasta per person? Select pasta type, number of servings, dry or fresh — get exact grams, water, and salt amounts

🍳 Cooking

Pizza Dough Calculator

Calculate exact flour, water, salt, and yeast for any pizza style. Yeast auto-adjusts for fermentation time and temperature. Baker's percentages included.

🍳 Cooking

Recipe Scaler

Scale any recipe up or down. Enter ingredients for 4 servings, change to 7 — every amount recalculates instantly with kitchen-friendly fractions.

🍳 Cooking

Rice to Water Ratio Calculator

Pick your rice type and number of servings — get the exact amount of rice and water. Covers basmati, jasmine, sushi, brown, wild, and more.

📐

Math

📐 Math

Circle Calculator

Enter radius, diameter, area, or circumference — instantly get all other circle measurements with step-by-step formulas

📐 Math

Cylinder Volume Calculator

Calculate the volume of any cylinder — pipes, tanks, barrels, cans. Enter diameter and height, get volume in liters, gallons, cubic meters, and more.

📐 Math

Percentage Calculator

Calculate any percentage — what is X% of Y, X is what % of Y, increase by %, discount, and percentage change between two numbers

✍️

Text & Writing

✍️ Text & Writing

Remove Duplicate Lines

Paste a list of lines — instantly remove duplicates. Keep first or last occurrence, case-sensitive or not, trim whitespace, sort the result.

✍️ Text & Writing

Text Diff Checker

Paste two texts and instantly see every difference — added, removed, and modified lines with word-level highlighting

🚗

Automotive

🚗 Automotive

Tire Size Calculator

Compare two tire sizes side by side — see diameter, circumference, sidewall height, and speedometer difference instantly

🚗 Automotive

Towing Capacity Calculator

Enter your vehicle's towing capacity, trailer weight, and cargo — instantly see if you're within safe limits

🐾

Pets & Animals

🐾 Pets & Animals

Cat Food Calculator

Calculate daily food portions for your cat based on weight, age, and activity — with guides for kittens, indoor cats, and seniors

🐾 Pets & Animals

Dog Calorie Calculator

Calculate your dog's daily calorie needs based on weight, neutered status, and activity level. Uses veterinary RER/MER formulas.

🐾 Pets & Animals

Dog Food Calculator

Calculate how much to feed your dog daily based on weight, age, activity level, and food type — with portion guides for puppies to seniors

🐾 Pets & Animals

Puppy Weight Calculator

Enter your puppy's current weight and age — get an estimate of their adult weight based on breed size

🌱

Gardening

🌱 Gardening

Fertilizer Calculator

Calculate how much fertilizer to apply based on lawn or garden area and N-P-K ratio. Get exact grams or pounds for any fertilizer product.

🌱 Gardening

Seed Spacing Calculator

Calculate how many plants fit in your garden bed — supports grid and offset patterns with presets for common vegetables

🌱 Gardening

Soil Calculator

Calculate how much soil you need for raised beds, planters, and gardens — get volume in cubic feet, liters, and bags

🌱 Gardening

Plant Watering Calculator

Enter garden area, plant type, and climate — get weekly watering needs in gallons or liters

📷

Photography

📷 Photography

Print Size Calculator

Calculate the maximum print size for your camera or image based on megapixels and DPI. See print dimensions for 150, 240, and 300 DPI quality levels.

📷 Photography

Canon EOS R5 Print Size Calculator

Calculate the maximum print size for Canon EOS R5 photos. 45MP sensor can print up to 27×18 inches at 300 DPI professional quality.

📷 Photography

iPhone 15 Pro Max Print Size Calculator

Calculate the maximum print size for iPhone 15 Pro Max photos. 48MP camera can print up to 27×20 inches at 300 DPI professional quality.

📷 Photography

Samsung Galaxy S24 Ultra Print Size Calculator

Calculate the maximum print size for Samsung Galaxy S24 Ultra photos. 200MP camera can print up to 54×41 inches at 300 DPI professional quality.

📷 Photography

Sony A7R V Print Size Calculator

Calculate the maximum print size for Sony A7R V photos. 61MP sensor can print up to 32×21 inches at 300 DPI professional quality.

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Fabric & Sewing

🧵 Fabric & Sewing

Crafts & Hobbies

🎨 Crafts & Hobbies

Cross Stitch Calculator

Calculate finished size, fabric needed, thread estimate, and stitching time for your cross stitch project. Supports Aida 11-22ct and Evenweave/Linen.