Free Alternative to Soulver

Numi is the closest free experience to Soulver—and for many users, it's just as good. The interface replicates the same 'pen and paper' approach that makes Soulver so intuitive: a dual-column layout where you type naturally on the left and see results instantly on the right. Type phrases like '$20 in euro - 5% discount' or 'meeting from 2pm to 4:30pm' and Numi calculates while you're still thinking.

The natural language processing feels remarkably similar to Soulver, handling everything from basic arithmetic to complex expressions with variables. Available for Mac, Windows, and Linux, Numi is cross-platform compatible and supports currency conversions with live rates, comprehensive unit conversions across length, area, volume, time, temperature, and even CSS units for web designers. The free version covers most users' needs; Numi Pro ($20) unlocks unlimited notes and iCloud sync, but the calculation engine itself is identical.

Parsify is a modern notepad-based calculator built from the ground up with privacy and extensibility as core principles. Unlike traditional calculators, Parsify lets you type free-form text mixed with calculations, seeing results update in real-time as you work. What sets Parsify apart is its plugin architecture—you can extend the calculator with custom functions, user-defined units, and specialized mathematical operations tailored to your specific needs.

The privacy-first design means all calculations happen locally on your device with no data sent to servers. Parsify supports advanced mathematical notation, variables that can reference each other, and multi-line expressions that make complex calculations readable. The interface is clean and distraction-free, focusing entirely on your work without unnecessary chrome.

SpeedCrunch takes a different approach than Soulver—instead of natural language, it's a keyboard-driven scientific calculator focused on precision and power. With up to 50 decimal digits of precision, it handles calculations that would lose accuracy in other tools. The 80+ built-in mathematical functions cover everything from basic trig to statistical distributions, and unlimited variable storage means you can build complex calculation workflows.

The interface uses syntax highlighting to make formulas readable at a glance, and smart auto-completion speeds up entry of function names and variables. It's completely free and open-source under GPL, running smoothly on Mac, Windows, and Linux. While the last major release was 2016, the codebase remains stable and functional on modern macOS versions.

Qalculate! is arguably the most powerful free calculator available, surpassing even Soulver in raw mathematical capability. It handles everything from basic arithmetic to symbolic calculations, derivatives, integrals, and complex equations. The unit system is extraordinarily comprehensive with automatic conversion between thousands of units across dozens of categories.

Currency rates for over 300 currencies update in real-time from multiple sources, making it more current than Soulver's 185 currencies. Qalculate! even includes plotting support for visualizing functions and data—something Soulver doesn't offer. The calculation engine supports arbitrary precision arithmetic, interval arithmetic with uncertainty propagation, and advanced mathematical concepts like matrix operations and statistical functions.

Used by students, scientists, and engineers worldwide, it receives active development with version 5.5.0 released in January 2025. It's more complex than Soulver but massively more capable for technical work.

Press Cmd+Space and start typing math—Spotlight calculates it instantly. Most Mac users don't realize how capable Spotlight is for quick calculations. It handles basic arithmetic operations, percentages, exponents, and even sophisticated unit conversions like '50 miles in km' or '100 USD in EUR' with live exchange rates.

The results appear as you type, updating in real-time as you refine your query. You can copy results with a single keystroke or click. While it lacks the multi-line notepad approach of Soulver, Spotlight is unbeatable for one-off calculations: no app to launch, no window to manage, just instant math from anywhere in your workflow. It supports natural language phrases like '15% tip on $45' or '3 hours 20 minutes from now', making it surprisingly versatile for daily calculation needs.

If you use Raycast as your launcher (and many Mac power users do), you already have solid calculation features at your fingertips. Type math expressions and get instant results, convert units between different measurement systems, and access your calculation history for reference. Raycast's calculator is more capable than Spotlight while being just as fast to access—no separate window required.

The calculation history feature means you can refer back to previous results, something Spotlight lacks entirely. Extensions expand Raycast's math capabilities further with specialized calculators for finance, programming, and scientific work. For users already in the Raycast ecosystem, it's a natural complement to Soulver-style calculations, handling quick math without context switching.

The Calculator app that comes with macOS is surprisingly capable if you know its hidden features. Press Cmd+2 for Scientific mode with trigonometric functions, logarithms, exponentials, roots, and statistical operations. Press Cmd+3 for Programmer mode with hexadecimal, binary, and octal conversions plus bitwise operations (AND, OR, XOR, NOT)—essential for developers.

The paper tape feature (Cmd+T) gives you a scrollable history of every calculation in the current session, effectively creating a calculation log. There's even RPN mode (Cmd+R) for fans of HP calculators who prefer reverse Polish notation. While it's not Soulver-style natural language, Calculator.app is genuinely useful for scientific and programming work. It speaks results aloud for accessibility, supports full keyboard navigation, and handles complex calculations that many users don't realize are possible in the default Mac calculator.

Calca is a markdown-powered text editor with built-in calculation abilities. As you type, it recognizes mathematical expressions and evaluates them inline, displaying results right next to your text. The markdown integration means you can format your documents with headings, lists, and emphasis while embedding calculations throughout.

Variables work across the entire document, so defining 'taxRate = 8.5%' at the top makes it available everywhere below. Calca is particularly elegant for financial planning, project estimates, and any scenario where you need to document your reasoning alongside the math. The real-time evaluation means changing one variable instantly updates all dependent calculations—like a lightweight spreadsheet embedded in your notes. While not free (it's around $25), it occupies a unique middle ground between Soulver's notepad style and a full spreadsheet.

Wolfram Alpha isn't a traditional calculator—it's a computational knowledge engine that understands questions in natural language and computes answers from curated data. Ask 'what is 15% tip on $47.50' and it shows not just the answer but a breakdown of the calculation. Query 'convert 50 miles to kilometers' and you get the conversion plus related information.

Wolfram Alpha handles symbolic math, differential equations, statistical analysis, and even generates plots and visualizations. The free web version is remarkably powerful, answering complex mathematical queries that would stump most calculators. Wolfram Alpha Pro ($7/month) adds step-by-step solutions, longer computation time, and downloadable results. While it requires internet access and isn't as quick as local calculators for simple math, Wolfram Alpha excels at complex problems and explaining mathematical concepts.