All tools run entirely in your browser. Your data never leaves your device. No signup, no tracking, no BS.
Add contact forms to your static site in 30 seconds. Free tier included.
Format, validate, and minify JSON with syntax highlighting.
Encode text or files to Base64, decode Base64 back to text.
Encode or decode URL components and query strings.
Encode special characters to HTML entities or decode entities back to text.
Escape or unescape backslash characters (\n, \t, \", \\) and JSON strings.
Upload an image and convert it to Base64 data URI. Copy or download.
Convert SVG code to CSS background-image data URI. URL-encode or Base64.
Validate JSON syntax with detailed error messages and line numbers.
Decode Base64 strings back to images. Preview and download PNG, JPEG, SVG.
Generate v4 UUIDs instantly. Bulk generate and copy with one click.
Build cron expressions visually with human-readable descriptions.
Generate placeholder text for mockups and designs. Paragraphs, sentences, or words.
Visual Unix file permission calculator. Toggle checkboxes to get octal and symbolic modes.
Generate QR codes from text or URLs. Download as PNG in multiple sizes.
Convert titles to URL-safe slugs. Custom separators, stop word removal, batch mode.
Visual table editor that generates Markdown table code. Add rows, columns, align.
Generate complete HTML meta tags including Open Graph and Twitter Cards.
Advanced crontab expression editor with natural language explanations and next run times.
Visual CSS Flexbox layout builder. Adjust properties and copy generated CSS code.
Generate cryptographically secure random passwords with custom length and character options.
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text.
Decode and inspect JSON Web Tokens. View header, payload, and expiry.
Generate JSON Web Tokens with custom payload and HMAC-SHA256 signing.
Inspect and analyze HTTP request/response headers. Security header checker included.
Test regular expressions with real-time match highlighting and flags.
Compare two texts line-by-line and see exactly what changed.
Write Markdown and preview the rendered output in real time.
Minify CSS to reduce file size or beautify it for readability. Shows compression ratio.
Format SQL queries with keyword uppercasing and proper indentation.
Convert between camelCase, snake_case, kebab-case, PascalCase, and more.
Convert Markdown to clean HTML source code. Copy and paste into your projects.
Paste JSON and auto-generate TypeScript interfaces. Nested objects supported.
Convert HTML to JSX. Auto-converts class to className, style strings to objects.
Minify JavaScript by removing comments, whitespace. Shows compression ratio.
Format and beautify HTML with configurable indentation.
Count words, characters, sentences, paragraphs, and reading time.
Paste JSON and click nodes to get JSONPath expressions. Tree view explorer.
Convert SQL queries to MongoDB query syntax. Supports SELECT, WHERE, JOIN, and more.
Compare two JSON objects and highlight structural differences. Nested diff support.
Convert Unix timestamps to human-readable dates and vice versa.
Convert colors between HEX, RGB, and HSL formats instantly.
Convert between binary, octal, decimal, hex, and any base (2-36). BigInt supported.
Convert between YAML and JSON formats. Perfect for configuration files.
Batch convert Unix timestamps to dates. Auto-detects seconds vs milliseconds. Timezone support.
Look up geolocation, ISP, timezone, and more for any IP address. Auto-detects your IP.
Convert between px, em, rem, pt, %, and vw. Set base font size and viewport width.
Convert JSON arrays to CSV or CSV to JSON. Auto-extract headers, download files.
Calculate aspect ratios. Input width & height or a ratio and one dimension.
Convert between TOML, JSON, and YAML formats. Perfect for Rust and Go config files.
Generate custom placeholder images with Canvas API. Set size, colors, text. Download PNG.
Complete HTTP status code reference. Search, filter by category, expand for details.
Generate full Tailwind CSS color palettes (50-950) from any base color. Copy config code.
Create letter-based favicons with custom colors and border radius. Download PNG in multiple sizes.
Preview how your page looks on Twitter, Facebook, and LinkedIn. Test Open Graph meta tags.
Preview Twitter Card appearance. Test summary and large image card types.
Visual CSS gradient builder. Linear, radial, conic gradients with live preview.
Visual CSS box-shadow generator. Multiple layers, live preview, copy CSS.
Regular expression quick reference. Search by category with examples.
Visual CSS Grid layout builder. Define rows, columns, gaps, and copy generated code.
Debug Open Graph tags by fetching any URL. Validate og:title, og:image, and more.
Calculate monthly payments, total interest, and full amortization schedule.
Calculate investment growth with compound interest. Visualize returns over time.
Calculate Body Mass Index with health category and weight range suggestions.
Calculate percentages, percentage change, and percentage of a number.
Calculate exact age in years, months, days. Next birthday countdown included.
Convert between yearly, monthly, weekly, and hourly salary. Tax estimation included.
Calculate daily calorie needs (TDEE) based on age, weight, height, and activity.
Calculate tips and split bills between friends. Custom tip percentages.
Calculate discount prices, savings, and stacked discounts with tax.
Calculate mortgage payments with down payment, PMI, and amortization.
Estimate US federal income tax with 2024 brackets and deductions.
Convert between 30+ world currencies with live exchange rates.
Calculate days between dates or add/subtract days from a date.
Calculate weighted GPA from courses, credits, and grades.
Calculate speed, distance, or time with multiple unit conversions.
Calculate area of rectangles, circles, triangles, and more shapes.
Estimate fuel cost for trips based on distance, efficiency, and price.
Convert times between 20+ major city time zones worldwide.
Generate random numbers with custom range, quantity, and sorting.
Advanced calculator with trig, log, and exponential functions.
Calculate percentage increase or decrease between two values.
Add or subtract hours, minutes, and seconds easily.
Add, subtract, multiply, and divide fractions with auto-simplification.
Calculate concrete volume needed for slabs, columns, and stairs.
Calculate electricity costs from wattage, hours, and rates.
Estimate blood alcohol content from drinks, weight, and time.
Estimate body fat percentage from body measurements.
Calculate optimal bedtime and wake time based on sleep cycles.
Predict ovulation date and fertile window from cycle data.
Calculate due date and pregnancy week from last period.
Calculate roof pitch angle and ratio from measurements.
Calculate compound interest with detailed growth charts and breakdowns.
Calculate simple interest on loans or investments quickly.
Generate full amortization schedules with principal and interest breakdown.
Calculate certificate of deposit returns with APY and compounding.
Calculate stock investment returns including dividends and splits.
Plan how much to save monthly to reach your financial goal.
Estimate retirement savings needed based on age, income, and lifestyle.
Calculate your net worth by listing assets and liabilities.
Create a monthly budget with income and expense categories.
Calculate return on investment percentage and annualized returns.
Find break-even point for your business with fixed and variable costs.
Plan debt repayment with snowball or avalanche strategies.
Calculate monthly car payments with trade-in and down payment.
Calculate how much down payment you need for a home purchase.
Compare renting vs buying a home over time with detailed analysis.
Calculate the impact of inflation on purchasing power over time.
Find your federal tax bracket and calculate effective tax rate.
Calculate Goods and Services Tax for inclusive and exclusive prices.
Calculate Value Added Tax for any amount and rate.
Convert hourly wage to annual salary and vice versa.
Estimate take-home pay after taxes and deductions.
Calculate conversion rate from visitors and conversions.
Calculate cost per mille (thousand impressions) for ad campaigns.
Calculate cost per click and optimize ad spend efficiency.
Calculate return on ad spend to measure campaign profitability.
Calculate customer lifetime value for SaaS and subscription businesses.
Calculate customer churn rate and revenue churn for SaaS.
Calculate markup percentage from cost and selling price.
Calculate profit margin, gross margin, and net margin percentages.
Calculate daily water intake based on weight, activity, and climate.
Calculate daily macronutrient needs for your diet goals.
Calculate running pace, speed, and finish time for any distance.
Calculate target heart rate zones for exercise and training.
Estimate calories burned by exercise type, duration, and intensity.
Calculate daily protein needs based on weight and fitness goals.
Calculate estimated due date and pregnancy milestones.
Convert dog years to human years with breed-specific calculations.
Convert cat years to human years with accurate age mapping.
Calculate carpet area needed for rooms with waste factor.
Calculate drywall sheets needed for walls and ceilings.
Calculate mulch volume needed for garden beds and landscaping.
Calculate swimming pool water volume for any shape.
Calculate snow load on roofs based on depth and snow type.
Calculate correct wire gauge for electrical circuits by amperage and distance.
Estimate solar panel system size and savings for your home.
Calculate gallons of paint needed for walls with doors and windows.
Calculate tiles needed for floors and walls with grout spacing.
Calculate fence materials: posts, rails, and pickets needed.
Calculate deck boards, joists, and materials for your project.
Calculate gravel volume and weight for driveways and paths.
Calculate soil volume needed for garden beds and raised planters.
Calculate concrete volume and dimensions for stairs and steps.
Calculate electricity costs for appliances based on usage and rates.
Convert between square feet and acres with common lot sizes.
Convert centimeters to inches and vice versa instantly.
Convert kilograms to pounds and vice versa with precision.
Convert shoe sizes between US, UK, EU, and CM systems.
Convert cooking measurements: cups, tablespoons, ml, ounces, and more.
Convert between Bytes, KB, MB, GB, TB, and PB instantly.
Calculate network address, broadcast, host range, and subnet masks.
Check WCAG AA/AAA compliance for any foreground and background color pair.
Count words, characters, sentences, paragraphs, and reading time.
Test your typing speed in WPM with accuracy tracking.
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