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Format JSON and CSV, convert text and units, or explore calculators with formulas and worked examples. Free to use, with no registration required.
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Health
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10Binomial Distribution CalculatorConfidence Interval CalculatorNormal Distribution CalculatorSample Size Calculator+1
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View AllFeatured Calculators
Everyday essentials and practical scenario tools
Conversion
Length Converter
Convert between metric and imperial length/distance units
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Conversion
Weight Converter
Convert between metric, imperial, and traditional Chinese weight units
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Conversion
Volume Converter
Convert between metric and imperial volume/capacity units
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Conversion
Data Storage Converter
Convert between different data storage units (Binary or Decimal)
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Conversion
Base64 Encoder / Decoder
Encode text or files (like images) into Base64 format, or decode Base64 back to plain text or visual images. Fully supports UTF-8 to prevent garbled text.
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Conversion
URL Encoder / Decoder
Encode or decode URLs and string components safely with full UTF-8 support.
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Conversion
MD5/SHA256 Hash Generator
Simultaneously calculate MD5, SHA-1, SHA-256, and SHA-512 cryptographic hashes of your input text.
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Daily Life
Percentage Calculator
Calculate percentages, percentage changes, and more
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Popular Online Tools
High-frequency utilities with instant in-browser processing
Image CompressorLossless & high-compression web image optimizer running in browser.WiFi QR GeneratorGenerate scan-to-connect QR codes for your home and office WiFi.Word & Character CounterDetailed character, word, sentence, and reading time analysis.Regex Tester & MatcherTest and debug regex patterns with live highlighting and matches.PX to REM ConverterFrontend responsive typography and spacing converter for CSS.Hash & Checksum GeneratorGenerate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly.
Popular Unit Conversions
Quick reference shortcuts for common length, weight, temperature, and data units
Find Tools by Scenario
Jump straight to calculators grouped around work, home, gear, and everyday decisions.
Business growth and founder math
Plan pricing, ad spend, unit economics, and creator revenue with focused calculators.
Freelance Hourly Rate CalculatorCalculate your target hourly rate based on desired income, expenses, and billable hours.ROAS & Break-Even CalculatorCalculate your Return on Ad Spend (ROAS) and determine your break-even point to ensure profitable advertising campaigns.SaaS LTV/CAC CalculatorCalculate Customer Lifetime Value (LTV), Customer Acquisition Cost (CAC) ratio, and payback period for your SaaS business.Social Media Revenue EstimatorEstimate your social media ad revenue based on video views and your niche\
Home, money, and risk planning
Decision calculators for energy payback, housing tradeoffs, savings buffers, and investing rules.
Solar Panel Payback CalculatorCalculate the breakeven point and return on investment (ROI) for installing a residential solar panel system.Rent vs. Buy CalculatorCompare the long-term financial costs and net worth outcomes of renting versus buying a homeEmergency Fund CalculatorCalculate how much emergency fund you should have and how to reach your goalRule of 72 & SIP CalculatorCalculate how fast your money will double and visualize the long-term compound growth of a Systematic Investment Plan (SIP).
Gear, maker, and technical utilities
Helpful calculators for PC builds, 3D printing, aquariums, photography, and network setup.
PC Power Supply CalculatorEstimate your PC peak power consumption and find the recommended power supply (PSU) wattage for your build.3D Printing Cost CalculatorEstimate the total cost of a 3D print based on filament usage, electricity, machine wear and tear, and your time/markup.Aquarium Volume CalculatorCalculate the volume of your aquarium and estimate the safe stocking level.Hyperfocal Distance CalculatorCalculate the hyperfocal distance for your camera lens to maximize depth of field.