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Why Utilix
Most calculator sites give you a number and move on. Utilix goes further.
Formula-first answers
Every result shows the formula, step-by-step working, and a concrete example — you understand why, not just what.
Private by default
Calculations run entirely in your browser. No data is sent to our servers — no tracking, no cookies, no surveillance.
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Everything in one place
110+ tools across 13 categories — finance, health, dev, design, AI, crypto, and more. One bookmark for every calculation need.
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Subnet / CIDR Calculator
Free IPv4 subnet calculator: enter an IP and CIDR prefix or subnet mask to get network, broadcast, host range, and wildcard mask instantly. No sign-up.
IP Address Converter
Convert IPv4 addresses between dotted decimal, binary, hexadecimal, and 32-bit integer formats instantly. Free browser tool — no uploads or sign-up required.
CIDR Subnet Splitter
Split a parent CIDR block into equal subnets. Enter 192.168.0.0/16 and target /24 for a full table of network, broadcast, and host ranges.
IPv6 Address Tools
Expand or compress IPv6 addresses, validate syntax, detect scope (global, link-local, loopback), and view binary hextets. Free browser tool — no sign-up.
Bandwidth / Transfer Time Calculator
Calculate file download or upload time from size and Mbps, or find data volume from speed and duration. Supports metric and binary units. Free, instant.
Port Number Reference
Look up IANA TCP and UDP port numbers by service name or number. See protocol support, official status, and descriptions for SSH, HTTPS, DNS, and more.
MAC Address Formatter
Format MAC addresses to colon, dash, or Cisco dot notation. Validate EUI-48 addresses and look up the OUI vendor prefix. Free browser tool — no sign-up.
Inflation Calculator
Calculate how inflation erodes purchasing power over time. Enter any amount, years, and inflation rate to see real value year by year. No sign-up needed.
Popular
LLM Cost Comparator
Compare AI model API costs side by side. Enter your token usage and see GPT-5, Claude 4, and Gemini 3 prices ranked cheapest to most expensive for your.
Finance & moneyMortgage Calculator
Estimate principal-and-interest from home price, down payment, rate, and term. Fully client-side — no account, uploads, or remote storage.
Finance & moneyLoan / EMI Calculator
Compute monthly EMI, total interest, and repayment from principal, rate, and term. Fully client-side — no account, uploads, or remote storage.
AI & LLM toolsAI API Cost Calculator
Calculate AI API usage cost for GPT-5, Claude 4, Gemini 3, and Llama 4 by tokens per request, daily volume, and yearly budget.
AI & LLM toolsLLM Token Counter
Count tokens and see context window usage for GPT-5, Claude 4, and Gemini 3. Paste text for token count, cost per request, and cost per 1,000 requests across.
Finance & moneyCredit Card Payoff Calculator
See exactly how long it takes to pay off your credit card and how much interest you'll pay. Enter your balance, APR, and monthly payment — no sign-up needed.
Finance & moneyDebt Payoff Planner
Compare the debt snowball and debt avalanche methods side by side. Enter up to 4 debts and see which strategy pays off your debt faster and saves the most.
Developer toolsJSON Formatter
Format, minify, sort keys, and validate JSON with readable errors. Fully client-side — no account, uploads, or remote storage.