There are many alternatives to OpalCalc for Windows if you are looking for a replacement. The best Windows alternative is SpeedCrunch, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to OpalCalc and many of them are available for Windows so hopefully you can find a suitable replacement. Other interesting Windows alternatives to OpalCalc are Qalculate!, Numara Calculator, Numbat and Qaltex.
SpeedCrunch is a free, fast, high precision open source algebraic calculator with an intuitive interface and many features, such as variables, syntax highlighting, functions, persistent input history & more.
Qalculate! is a multi-purpose cross-platform desktop calculator. It is simple to use but provides power and versatility normally reserved for complicated math packages, as well as useful tools for everyday needs (such as currency conversion and percent calculation).
A simple but powerful notepad calculator which evaluates expressions as you type.
High precision scientific calculator with full support for physical units (web and terminal versions).
Qaltex is a tape-like calculator with straightforward interface and a lot of features. It is inspired by many other similar applications, but solves their disadvantages and at the same time it is empowered with some unique options and widgets.
Numi is a handy calculator app for macOS. It allows to describe tasks the natural way and instantly get an accurate answer. For example, $20 in euro - 5% discount or today + 2 weeks. Numi is not limited to simple calculations, it can solve expressions of any complexity, with...
A simple yet powerful calculator that includes standard, scientific, and programmer modes, as well as a unit converter. It's the perfect tool to add up a bill, convert measurements in a recipe or other project, or complete complex math, algebra, or geometry problems.
Next generation notepad-based calculator, built with extendibility and privacy in mind. Works on Windows, macOS and Linux.
A text calculator for natural language expressions, variables & unit conversions, with a vim-style TUI. Inspired by Numi.
Ever wanted to work something out, but your default calculator isn't powerful enough, and it's not worth creating a spreadsheet for?
A kickass, open-source calculator that lets you do calculations and unit conversions naturally, with features like:
Do you really need your calculator's on-screen number pad? (You know, the virtual keyboard?)
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Very, very similar to opal. For less strenuous calculations speed is better. For more complex calculations, opal, full version is better with a slightly higher learning curve.