Soulver 4 casts a wider calculating net

The almost-natural-language notepad calculator Soulver’s latest release adds better tools for calculating durations or intervals between dates and times, planning travel itineraries, tracking inflation, finding distances, performing bandwidth math, and splitting restaurant bills or other expenses. That’s not all, but a good starting list. Should it do all these things? A point we could argue about! But many of the features it offered in the past, and several of the new ones it provides, previously required one or more web searches to find a tool or to pull together disparate information. That’s welcome.

Soulver 4’s release comes at an interesting time, when many people have turned to chatbots and Google’s search dialog—and soon will turn to Siri AI—to answer questions that are better written out or spoken than described as just numbers or operators.

This significant update succeeds in bringing a sort of authoritative basis to stuff you need to calculate or convert. Behind the scenes, there’s no inference or autocompletion—it’s numbers, baby, all the way down. However, the developers aren’t unaware of the AI glow-up. They’ve addressed it in an interesting way, making it easy for agents to ask questions of Soulver!

Soulver 4 lets you perform a variety of calculations that transform units, days, distances, and vastly more than I can show.

How many bushels in a peck as I travel a furlong faster than a parsec?

Soulver has filled a gap for me in my calculating needs since I dug into the subject in 2015. While I love PCalc and use it for regular and advanced calculator needs, Soulver is where I go when I need to mix things up.1

PCalc and Soulver offer overlapping Venn diagrams of what’s possible in number space, but they are distinctly different beasts at heart. Where PCalc mostly calculates within a calculator-style interface, Soulver mostly offers a way to make sense of numbers, units, percentages, time, intervals, and much more. I think of it as a “take stuff in various units or other formulations and then produce an output in a way I want” tool.

I sometimes go days without using Soulver, and then find myself typing in an array of calculations. For instance, as a tiny print book publisher (it’s just me), I am often dealing with the weight of paper, the weight of books, the cost of shipping, and other variables. The number of sheets I have in some of my Numbers documents is alarming, but I often need conversion that sounds like a story problem: “The printer in Canada is giving me paper weight in gsm (grams per square meter). I know the book’s area per page (typically in inches). I need to calculate the weight of 1,000 copies in pounds.” I can type the query faster than I describe it. For instance, I need to estimate the weight of a new book based on the weight and page count of one I am holding:

(6 inches x 9 inches) / (5.875 inches × 8.25 inches) × (352 / 204) × 302g in lbs

Version 4 continues to offer all of what I consider its basics. You type out numbers and units with operators between them. You can set variables, add comments, and drag results into subsequent lines as part of further calculations. You can force-convert units, as above, telling it to use a metric unit instead of imperial, or to use a different unit scale. Say you want inches instead of feet, or kilograms instead of pounds.

Because it’s a notepad, your work is persistent. You can use Soulver to create the equivalent of tabs within sheets, collected into a “sheetbook.” This is somewhat like the Notes app, and it lets you organize calculations into projects and sub-projects. I have a monolithic sheet I use for essentially everything. Soulver can store files locally or sync via iCloud.

I use Soulver for a lot of different purposes, sometimes several times a day.

Where version 4 starts to diverge from previous releases is in what feels like a baroque set of options that aren’t stapled on, but most require a bit more effort to get the nuance and make them work for you.

How much did Minions & Monsters make in 1940 dollars?

It took me a few weeks to write this review, quite honestly, because every time I looked at the upgrade page, my eyes glazed over as I thought about how to best present this. I mean, the release notes page is broken into ten sections. The answer—which didn’t require Soulver 4—is that I need to cherry-pick more than usual for an app to give you the flavor.

Here are a few new elements that will keep me away from search engines and other resources more than any other:

Inflation calculation. As a historian, and as somebody who just wants to use his numeracy to interpret the world, I find myself jumping for an inflation calculator all the time.2 You need an online source, as it has to have a table of the historical values to provide the correct cumulative percentage between two years or dates. Because of the relatively high inflation in developed nations since the start of the pandemic, I find myself trying to understand why I’m staring at a jar of peanut butter and can’t comprehend what it costs now. (Soulver currently does annual inflation calculations, but will add monthly data in a future update.)

It’s a date: Date math is the hardest math, in my experience. Soulver previously let you perform the magic of subtracting one date from another or adding days to a date to figure out the right month, day, and year. In the update, you can do more tricks, like figuring out work hours (set by default, and you can change) in periods of time or differences, calculating relative to cultural and religious holidays, finding the number of daylight hours in a particular place, and (as should be obvious so far) much more. As a person of the Jewish faith, I honestly never know when Hanukkah starts, and Soulver doesn’t appear to know either. (Soulver says Hanukkah is coming in a future update.) However, it does include Christmas and Ramadan; there’s no list of this category, but you can look in Soulver: Settings: Dates & Times and click Public holidays to see that list, set by your region.

How far away? I don’t know about you, but I regularly want to know the distance between two places, sometimes nearby, sometimes far away. Soulver 4 lets you ask, distance between [place name] and [place name], and get the proper curvature-adjusted distance. (I have a proviso about this that you can read at the end.)

How long to upload? I’ve used Soulver for bandwidth and file-transfer time calculations since I first installed it. With the latest release, you don’t have to punch in nearly as many units or conversions to get an answer to a question like time to upload 1TB at 900Mbps. (Answer: 2.47 hours.)

Elements you’ll find added or improved that I haven’t found a particular use for yet but seem significant include:

Better formatting: You can highlight expression lines with one of eight preset colors, as well as add divider lines. This makes data in sheets easier to parse. In addition to the previously available export function, Soulver 4 lets you email sheets to yourself with full HTML formatting.

You can plan itineraries in Soulver 4, which will calculate hours or days and reveal when you haven’t left enough time.

Trip planning: I’ll be honest that this feature looks powerful, but requires breaking out of the Soulver mold, as it uses a multi-line approach by defining the top and bottom of the trip range as a “time point” via the contextual menu. However, because of how it calculates time intervals and provides warnings if the duration you’ve set doesn’t fit, you can use it for short itineraries (getting to the airport on time) or planning a long trip.

It’s a fair division, given how much I ate at this lunch.

One of the many ways tags can be used in Soulver 4 for tracking line-based expenses without resorting to a spreadsheet.

Tags workflow: Coders are amazing people, and you can see that in the simplicity and complexity of this tagging feature. When you tag a line with a hashtag and a tag name, the associated value can be summed, and operations can be performed on it. For instance, you can tag everyone’s individual orders on a dinner bill, add in tax and tip, and then have it divvied out. But that’s just one example. A spreadsheet could be easier, but it can also be overkill.

A command-line interface: If you’re the kind of person who doesn’t like a GUI, a command-line approach to Soulver might fit you, but the developers created it mostly to allow a simple way for you to have various other things, whether scripts, editor plug-ins, or coding agents, use Soulver as a kind of engine of numerical accuracy.

Weather goest thou?

Soulver is a $59 one-time purchase and gives you access to Mac, iPhone, and iPad versions. (There’s a 60-day free trial to test it out.) While that might seem high, I think given inflation—wink, wink—that’s comparable to the $30–$40 we might pay for a single-platform great utility in 2010! The iPhone version can be purchased on its own for $15. Soulver 3 owners pay $29 to upgrade to version 4. You can also get Soulver 4 via the $15 a month Setapp subscription, and have full access to it and over 330 other apps.

But you might run into one not-quite-hidden subscription option if you make certain weather or stock queries. With the App Store version of Soulver, $26 a year gives you access to what the app labels Live Weather (a number of current metrics), Live & Historical Stocks (a deep trove of data and real-time), and Inline Knowledge Assistant (which lets you use Wolfram|Alpha). It’s included at no extra cost for Setapp subscribers.

An optional subscription provides access to more data, but most people won’t need it.

I ran afoul of an aspect of this in testing, as Soulver (as of 4.0.2) included about the top 700 most populous cities and leaned on Wolfram for more, but didn’t prompt me as to why it couldn’t identify a city I mentioned. Developer Zac Cohan said the next minor update will add dynamic place-name lookups as part of the base price to reduce confusion and better fit the user base.

This subscription is not at all necessary to use Soulver 4, and Zac says the vast majority of Soulver users don’t need it. However, the cost to provide the data and services is too high to include for all users, hence the subscription to defray those costs.

Disclosure: I wrote a version of the PCalc manual several years ago for a flat fee. ↩

Minions & Monsters reportedly grossed $450 million as of July 1, 2026, which is $18.7 million in January 1940 dollars.) ↩