This online calculator allows user to experiment with regular expressions.

The Email Finder calculator allows users to search for and extract email addresses from a block of text using a regular expression.

The phone number extractor calculator is a useful tool that extracts phone numbers from a large block of text.

Hack the three-digit code

This article describes process of calculator creation and how to set output value.

This article describes the process of adding translation support to the calculator, so it can be translated into different languages.

This article describes the process of adding custom errors to the calculator

This article describes how to make calculator which outputs results in table format

This article describes how to control visibility of input and output controls in a calculator

This article describes how to create calculator with virtual keyboard using SVG image

This article describes how to create calculator with image map using SVG image

Simple image map of France regions to illustrate usage of SVG image maps

This article describes process of reusing another calculator's logic (algorithm) in your calculator.

This calculator converts the date to epoch timestamp in milliseconds, that is, milliseconds since standard epoch of 1/1/1970, as used, for example, in JavaScript.

How to use big number input and PCR library.