Free Online Calculators

Calculate total AI API costs across multiple models and request volumes.

Check if your prompts fit within any AI model context window.

Estimate AI API costs for GPT, Claude, Gemini, and LLaMA.

Count tokens for GPT, Claude, Gemini, and LLaMA models.

Convert rate limits between time windows and estimate monthly API costs.

Calculate mean, median, mode, range, and standard deviation.

Perform arithmetic on binary numbers. See results in binary, decimal, and hex.

Convert between Bytes, KB, MB, GB, TB, and PB with all equivalents shown at once.

Count characters, unique characters, and find the most frequent character in text.

Upload a file and calculate its MD5, SHA-1, SHA-256, and SHA-512 checksums.

Calculate token usage against Claude up to 1M context windows.

Calculate Anthropic Claude API costs for Sonnet, Opus, and Haiku.

Count tokens for Claude Sonnet 4.6, Opus, and Haiku models.

Calculate the exact difference between two dates.

Convert a date and time to Unix timestamp in seconds and milliseconds.

Convert between Ethereum gas price units: wei, gwei, kwei, mwei, and ether.

Calculate token usage against Gemini 1M and 1M context windows.

Calculate Google Gemini API costs for 1.5 Pro, Flash, and 1.0 Pro.

Count tokens for Gemini 2.5 Pro, Flash, and Gemini 2.0 Flash models.

Perform arithmetic on hexadecimal numbers. See results in hex and decimal.

Calculate the aspect ratio from width and height, or compute a missing dimension from a known ratio.

Calculate CIDR notation, total IPs, and subnet mask from a start and end IP address.

Convert between mm, cm, m, km, inches, feet, yards, and miles.

Count total lines, blank lines, non-blank lines, and average line length.

Calculate token usage for LLaMA 3.1 models with 128K context.

Estimate LLaMA 3.1 API costs on hosted inference providers.

Count tokens for LLaMA 4 Scout, Maverick, and LLaMA 3.2 models.

Check if your prompts fit within GPT-4o and GPT-3.5 context windows.

Calculate GPT-4o, GPT-4.1, and GPT-3.5 API costs.

Count tokens for GPT-4o, GPT-4.1, and GPT-3.5 models.

Calculate percentages: find X% of Y, what % X is of Y, or % change.

Check if a number is prime and generate primes up to N.

Calculate probability as fraction, decimal, percentage, and odds.

Solve ratios, simplify A:B, and find missing values.

Show how long ago or how far in the future a date is.

Find out how many days until an SSL certificate expires. Paste a PEM or enter a date.

Calculate network address, broadcast, hosts, and subnet mask from IP/CIDR notation.

Convert between Celsius, Fahrenheit, and Kelvin temperature scales.

Convert Unix timestamps to human-readable dates and vice versa.

Convert between token base units and display units with custom decimal support for any ERC-20.

Convert weights between milligrams, grams, kilograms, ounces, pounds, and metric tons.

Count words, characters, sentences, and lines in any text.