Estimate tokens for GPT-4o, Claude, and Llama from any text. Shows context window usage, estimated API cost, and includes Python tiktoken snippets.

Test and debug regular expressions in real time with match highlighting. Supports global, case-insensitive, multiline, and dotAll flags. Includes Python re snippets.

Compute precision, recall, F1, F2, accuracy, specificity, MCC, and NPV from TP/TN/FP/FN values. Includes scikit-learn code.

Paste a list of numbers and instantly get mean, median, mode, std dev, variance, IQR, skewness, and more. Includes NumPy and Pandas snippets.

Format and beautify SQL queries instantly. Uppercases keywords, puts each clause on its own line, and indents columns and conditions.

Convert CSV to JSON and JSON to CSV in your browser. Handles quoted fields, nested values, and automatic type coercion. Includes Pandas snippets.

Validate, format, and convert YAML files online. Supports YAML → JSON and JSON → YAML. Includes PyYAML Python code snippets.

Encode text to Base64 or decode Base64 strings instantly. UTF-8 safe. 100% client-side — nothing leaves your browser. Includes Python and JS snippets.

Convert strings between camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE_CASE, Title Case, and more. Instant copy for each variant.

Multiply two matrices up to 6×6 with step-by-step results. Understand the shapes behind neural network layers. Includes NumPy and PyTorch code.

Pretty-print, validate, and minify JSON instantly. 100% client-side — your data never leaves the browser. Includes Python and JS code snippets.

Compare two text files or code blocks side-by-side with GitHub-style red/green highlighting. Generate a shareable diff link for teammates.

Build a cron expression from plain English dropdowns, or paste any expression to translate it to a human-readable schedule. Includes a full cron cheat sheet.

Convert between Unix timestamps and human-readable dates. Includes Python, JavaScript, Pandas, and SQL snippets.

Find what day number any date falls on (1–366), or convert a day number back to a calendar date. Handles leap years automatically.

Find the day number of any date, track how much of the year has elapsed, or calculate how many years ago a given year was.

Generate a word cloud from any text. Visualize term frequency and explore NLP preprocessing.