SmartTools

Exact age in years, months and days between a birth date and a reference date (default: today). Runs on smart-tools.xyz.

Convert a value between angle units. Units: ° (Degree), rad (Radian), grad (Gradian), mrad (Milliradian), rev (Turn), ′ (Arcminute), ″ (Arcsecond). Calculation runs on smart-tools.xyz.

Convert a value between area units. Units: km² (Square kilometer), m² (Square meter), cm² (Square centimeter), mm² (Square millimeter), ha (Hectare), ac (Acre), mi² (Square mile), ft² (Square foot), yd² (Square yard), in² (Square inch). Calculation runs on smart-tools.xyz.

Simplify a width×height ratio and scale to a new width or height. Runs on smart-tools.xyz.

Encode text to Base64 or decode Base64 back to text, UTF-8 safe, with an optional URL-safe alphabet. Runs on smart-tools.xyz.

Body Mass Index and category. system=metric: weight_kg, height_cm. system=imperial: weight_lb, height_ft (+height_in). Runs on smart-tools.xyz.

Basal metabolic rate (Mifflin–St Jeor) and daily calories (TDEE = BMR × activity). Runs on smart-tools.xyz.

Body fat percentage by the US Navy (Hodgdon–Beckett) method, metric measurements in cm. Females require hip_cm. Runs on smart-tools.xyz.

Convert text to UPPER, lower, Title, Sentence, camelCase, PascalCase, snake_case, kebab-case or CONSTANT_CASE. Runs on smart-tools.xyz.

Convert a color between HEX, RGB and HSL. Accepts #hex, rgb()/rgba(), hsl()/hsla(). Runs on smart-tools.xyz.

Future balance and interest earned: A = P(1 + r/n)^(nt). Runs on smart-tools.xyz.

Parse a 5-field cron expression (minute hour day-of-month month day-of-week) into a plain-English description. Runs on smart-tools.xyz.

Parse CSV/TSV text (auto-detecting tab, semicolon or comma delimiter) with a header row into an array of JSON objects. Runs on smart-tools.xyz.

Turn CSV/TSV rows into SQL INSERT statements with standard double-quoted identifiers and escaped values. Runs on smart-tools.xyz.

Convert a value between data units. Units: bit (Bit), B (Byte), kB (Kilobyte), MB (Megabyte), GB (Gigabyte), TB (Terabyte), KiB (Kibibyte), MiB (Mebibyte), GiB (Gibibyte), TiB (Tebibyte). Calculation runs on smart-tools.xyz.

Difference between two dates: calendar years/months/days, total days, weeks and weekday count. Runs on smart-tools.xyz.

Final price after one or two successive discounts, plus amount saved. Runs on smart-tools.xyz.

Estimated due date by Naegele's rule (+280 days from last period, adjusted for cycle length). Runs on smart-tools.xyz.

Running cost of an appliance per day, month and year from its wattage. Runs on smart-tools.xyz.

Convert a value between energy units. Units: J (Joule), kJ (Kilojoule), cal (Calorie), kcal (Kilocalorie), Wh (Watt-hour), kWh (Kilowatt-hour), BTU (British thermal unit), ft·lb (Foot-pound), eV (Electronvolt). Calculation runs on smart-tools.xyz.

Compute a SHA-1/256/384/512 hex checksum of provided text or base64 bytes. Runs on smart-tools.xyz.

Exact arithmetic on two fractions (a/b op c/d), reduced to lowest terms. op is one of + - * /. Runs on smart-tools.xyz.

Fuel needed and trip cost. system=metric: distance km, consumption L/100km. system=imperial: distance miles, consumption mpg. Runs on smart-tools.xyz.

Build a .gitignore from curated templates for Node, Python, Go, Rust, macOS, VS Code and more. Runs on smart-tools.xyz.

Weighted grade point average from letter grades (US 4.0 scale, +/-) or numeric grade points and credit hours. Runs on smart-tools.xyz.

Build a CSS linear or radial gradient background declaration from two or more colors. Runs on smart-tools.xyz.

Hash text with SHA-1, SHA-256, SHA-384 or SHA-512 (hex, over UTF-8 bytes). MD5 is not supported. Runs on smart-tools.xyz.

Convert a height between centimetres and feet/inches. Give cm, or feet (with optional inches). One inch = 2.54 cm exactly. Runs on smart-tools.xyz.

Time worked between two clock times (handles overnight), minus a break, with optional pay. Times as HH:MM. Runs on smart-tools.xyz.

Generate Apache .htaccess rules: force HTTPS, www redirect, caching, gzip, hotlink protection and more. Runs on smart-tools.xyz.

Escape the five special HTML characters (optionally all non-ASCII) or decode named and numeric HTML entities back to text. Runs on smart-tools.xyz.

Healthy weight range (BMI 18.5–24.9) plus Devine, Robinson, Miller and Hamwi formula estimates, from height in cm. Runs on smart-tools.xyz.

Validate and pretty-print or minify JSON, reporting the line and column on a parse error. Runs on smart-tools.xyz.

Decode a JSON Web Token's header and payload (base64url). Does NOT verify the signature — that needs the secret/key. Runs on smart-tools.xyz.

Fix text typed in the wrong keyboard layout between English QWERTY and Ukrainian ЙЦУКЕН. Runs on smart-tools.xyz.

Convert a value between length units. Units: km (Kilometer), m (Meter), cm (Centimeter), mm (Millimeter), µm (Micrometer), mi (Mile), yd (Yard), ft (Foot), in (Inch), nmi (Nautical mile). Calculation runs on smart-tools.xyz.

Monthly payment, total repayment and interest for an amortising loan (annuity formula). Runs on smart-tools.xyz.

Generate placeholder lorem ipsum text by paragraphs, sentences or words. Runs on smart-tools.xyz.

Profit, margin (share of price) and markup (share of cost) from cost and selling price. Runs on smart-tools.xyz.

Build a padded GitHub-flavored Markdown table from CSV/TSV text (first row is the header). Runs on smart-tools.xyz.

Generate SEO, Open Graph and Twitter Card HTML meta tags for a page. Runs on smart-tools.xyz.

Monthly mortgage payment including optional down payment, property tax and insurance (PITI). Runs on smart-tools.xyz.

Convert an integer between bases 2–36 (binary, octal, decimal, hex and more), exact for 64-bit values via BigInt. Runs on smart-tools.xyz.

Running pace per km and per mile, plus speed, from distance and time. Runs on smart-tools.xyz.

Generate a cryptographically strong random password with configurable length and character sets. Runs on smart-tools.xyz.

Percentage operations. operation=percent_of: a% of b. operation=is_what_percent: a is what % of b. operation=change: percent change from a to b. Runs on smart-tools.xyz.

Convert a value between pressure units. Units: Pa (Pascal), kPa (Kilopascal), hPa (Hectopascal), bar (Bar), atm (Atmosphere), psi (Pound per sq inch), mmHg (Millimeter of mercury), inHg (Inch of mercury). Calculation runs on smart-tools.xyz.

Generate cryptographically random integers in a range, optionally unique and sorted. Runs on smart-tools.xyz.

Test a JavaScript regular expression against text and return every match with its captured groups. Runs on smart-tools.xyz.

Remove duplicate lines, with optional trim, case-insensitive matching, sorting or keeping only the duplicated lines. Runs on smart-tools.xyz.

Build a robots.txt: allow or block all, custom disallow paths, AI-crawler blocking, crawl-delay and sitemap. Runs on smart-tools.xyz.

Convert pay between hourly, daily, weekly, biweekly, monthly and annual. Runs on smart-tools.xyz.

Evaluate a math expression with correct order of operations: + - * / % ^, parentheses, and functions (sqrt, sin, cos, tan, ln, log, exp, min, max, factorial via !). Constants pi, e. Angles in radians. Runs on smart-tools.xyz.

Turn text (incl. Ukrainian and accented Latin) into a clean URL slug; each non-empty line becomes its own slug. Runs on smart-tools.xyz.

Convert a value between speed units. Units: m/s (Meter per second), km/h (Kilometer per hour), mph (Mile per hour), ft/s (Foot per second), kn (Knot). Calculation runs on smart-tools.xyz.

Mean, variance and standard deviation (both sample and population) of a list of numbers. Runs on smart-tools.xyz.

IPv4 subnet details: network, broadcast, mask, wildcard, host range and count for an IP and prefix. Runs on smart-tools.xyz.

Convert a pasted HTML <table> or delimited (tab/semicolon/comma) table into clean CSV. Runs on smart-tools.xyz.

Convert a value between temperature units. Units: °C (Celsius), °F (Fahrenheit), K (Kelvin), °R (Rankine). Calculation runs on smart-tools.xyz.

Count characters (with and without spaces), words, lines, paragraphs and estimated reading time. Runs on smart-tools.xyz.

Line-level diff of two texts (LCS): counts of added/removed lines plus a marked-up line list. Runs on smart-tools.xyz.

Convert a value between time units. Units: µs (Microsecond), ms (Millisecond), s (Second), min (Minute), h (Hour), d (Day), wk (Week), mo (Month), yr (Year). Calculation runs on smart-tools.xyz.

Convert between a Unix timestamp and an ISO 8601 date (UTC). direction=to_date: epoch → date; to_timestamp: date → epoch. Runs on smart-tools.xyz.

Tip amount, total and per-person split for a bill. Runs on smart-tools.xyz.

Transliterate Ukrainian Cyrillic to Latin by the official KMU #55 passport standard. Runs on smart-tools.xyz.

Solve a triangle. mode=sss: three sides a,b,c. mode=sas: two sides a,b and the included angle angle_c (degrees). Returns sides, angles (degrees), area and perimeter. Runs on smart-tools.xyz.

Compare price per unit of two packs and report which is cheaper. Runs on smart-tools.xyz.

Percent-encode or decode a URL. mode=component escapes /?&= (for a value); mode=full keeps them (for a whole address). Runs on smart-tools.xyz.

Append encoded UTM campaign parameters to a URL, preserving any existing query and fragment. Runs on smart-tools.xyz.

Generate one or more random version 4 (RFC 4122) UUIDs. Runs on smart-tools.xyz.

Add VAT to a net amount or remove it from a gross amount. Runs on smart-tools.xyz.

Convert a value between volume units. Units: m³ (Cubic meter), L (Liter), mL (Milliliter), gal_us (US gallon), gal_uk (UK gallon), qt (US quart), pt_us (US pint), pt_uk (UK pint), cup (US cup), fl oz (US fluid ounce). Calculation runs on smart-tools.xyz.

Compute the WCAG 2.x contrast ratio between two hex colors and whether it passes AA/AAA for normal and large text. Runs on smart-tools.xyz.

Convert a value between weight units. Units: t (Tonne), kg (Kilogram), g (Gram), mg (Milligram), lb (Pound), oz (Ounce), st (Stone). Calculation runs on smart-tools.xyz.