Best Open Source Date Calculators 2026

Date Calculators

Date Calculators Scientific/Engineering Clear Filters

Browse free open source Date Calculators and projects below. Use the toggles on the left to filter open source Date Calculators by OS, license, language, programming language, and project status.

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1

pcalc

NOTE: Moved to https://github.com/vapier/pcalc Pcalc is a command line calculator handling HEX DEC OCT BIN. It can process a script, save variables to file, full math parser, parentheses, exponential, sin/cos, sqrt, date, inch/mm celsius/f, compound expressions ...

Downloads: 13 This Week

Last Update: 2022-02-23
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2

Julian Date calculator

A simple command to convert calendar dates to julian dates. Quite useful in timing situations where you need elapsed time between dates. Also useful for astronomy applications.

Downloads: 7 This Week

Last Update: 2013-04-08
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3

UltimateCalculator

Basic Scientific Calculator

This software has four major modes- Simple, Scientific, Base & Equation. It also has Unit Converter, Date Calculator & Prime Number Generator.

Downloads: 0 This Week

Last Update: 2017-05-29
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4

VremyaMetr

VremyaMetr - a tool to measure time and study it's laws. Remind about events + Date calculator + Work with periods + Create table + Kalachakra.

Downloads: 0 This Week

Last Update: 2013-04-05
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