Numlex

A notepad calculator: type plain lines, get live, checked results — natural math, variables, percentages, dates, unit and currency conversions, and reusable live answer tokens.

Download the latest release

Features

Variables & Functions	Natural Calculations
Name values, apply functions, and totals stay live	Arithmetic, percentages, section totals and dates — as plain lines
Units & Currencies	Linked Answers
Convert distance, temperature, mass and currency in one line	Reuse any result as a bubble that stays in sync

Natural calculations

For the full, exhaustive reference of every construct — line forms, operators, functions, bases, percentages, money, units, currencies, dates, network queries, number presentation — see the docs/SYNTAX_REFERENCE.md canonical reference (documents current main) and the documentation index for the settings and appearance guide, docs/EXPORT_AND_PRINT.md for PDF export and printing, and docs/UPDATES.md for the secure in-app update model. The published documentation lives at .

Numlex reads ordinary notebook text — no formula syntax, no cell references. Each line is evaluated strictly; anything it cannot parse stays quiet instead of guessing.

hotel = 1240          1,240
hotel + 10%           1,364
$240 + 10% tip        $264.00
sqrt(144)             12
room = 180 × 4        720
round(room / 3, 2)    240
sum(1, 2, 3)          6
20 km to meter        20,000 m
100 C to F            212 F°
Jan 10 + 12 days      Jan 22

Every line above runs through the real engine — these are its exact, deterministic outputs, with no live rates involved. Declare values with name = expression, use percentages and money with the same grammar ($240 + 10% tip), and do date arithmetic on plain month names (Jan 10 + 12 days). Named money reads naturally too: apple = 5$ prices one apple, and 2 apples + 3 apples totals in dollars.

Currency codes are case-insensitive: 500 usd, 500 UsD and 500 USD all mean 500 US dollars (usd, eur, gbp, … — any of the 166 supported ISO codes). A line may combine currencies with + and -: the first money operand sets the result currency and every other operand is converted into it with the current rates, so with 1 EUR = 1.1 USD 500 usd - 300 eur is $227.27. Symbols and codes mix freely ($500 - 300 eur, 500 usd - €300), and plain scalars or percentages keep their meaning (500 usd - 20 = $480.00, 500 usd - 10% = $450.00). Currency × currency and currency ÷ currency stay errors (never a silent USD²), money × scalar and money ÷ scalar still work, and physical units still never convert implicitly. If the needed rate pair is missing, the answer is the explicit Rates unavailable state — never a guessed number, a partial sum or a stale rate. The same rules apply to named values and to answer tokens: balance = 500 usd - 300 eur stores US dollars, and TOKEN - 300 eur converts into the token's currency. Constants are offline, so a single-currency constant (Rent = 500 usd) resolves normally while a mixed-currency constant stays inactive.

Built-in math functions

The engine shares one pure function registry across every scalar path — free expressions, assignments, constants and unitless answer tokens. Names are case-insensitive, arguments are full expressions (nesting included), and a function-shaped line is strict: an unknown name, a bad arity, a bad comma or a domain failure is a precise error, never a guess.

• sqrt, abs, round(x) / round(x, d) (ties round away from zero)
• min, max, sum, average — variadic, one or more arguments
• pow(b, e) — same finite contract as the ^ operator
• ln(x), log(x) (base 10), log(x, b), log10(x)
• sin, cos, tan — radians; asin, acos, atan
• radians(d) and degrees(r) — explicit unit helpers

Section totals

A standalone total line sums the unitless calculation answers above it — since the sheet start or the previous total — and starts a fresh section below. The answer renders semibold under a gray rule placed exactly between the neighboring answers, and it behaves like any other answer: Copy, per-answer rounding and tokens all work, and wrapped logical lines keep their gutter number centered on the block. Money, unit-bearing quantities, booleans, dates and error rows never enter a section total.

The window also has a persistent bottom Total panel (turn it off under Settings → General → Show total bar). It is a separate, dimension-agnostic contract: it adds the evaluated magnitude of every ordinary scalar answer row once — unitless numbers, unit-bearing quantities (2 kg), money ($3), named scalars and exact integers — and shows one plain unitless number with no unit conversion, no FX normalization and no unit or currency suffix (2 kg, $3 and 4 EUR total 9). Inline total rows are excluded so the two totals never double-count, and booleans, dates, locations/DMS, error and blank rows do not contribute. Per-answer rounding and number-format overrides never change the bottom Total; it follows the global notation and regional settings.

Conversions

Write 10 km to meter — in works just as well (10 km in meter).

• Around 290 measurement units across length, area, volume, mass, time, speed,

• 166 fiat currencies with live rates: codes (10 EUR to USD), symbol forms

• Rates are cached locally for an hour; if the network is unavailable, Numlex keeps

Type weather in London for the current 2 m temperature in Celsius degrees (shown C°). The lookup goes to Open-Meteo with no key and no location permission — only the city you typed is ever sent. Readings are cached for ten minutes, and the last good value keeps showing if the next refresh fails, so a flaky connection never blanks your sheet. The city name is tinted exactly like any other unit, in Light, Dark and custom styling alike.

Answer tokens

Double-click any answer — or type an operator on a new line — and Numlex inserts a live token at the caret or selection. A token is a small bubble that always displays the current value of its source line: change the source and the bubble updates immediately. Several distinct bubbles may reuse the same earlier line — each keeps its own identity and follows the live value, as in the screenshot above. If a source line stops evaluating, its tokens stay in place and show the remembered Line N label instead of a stale number.

Answer menu

Right-click (or Control-click) any answer for its native menu: Copy Answer puts the exact displayed value on the clipboard; the discrete 0…10 dp slider re-rounds just that answer without touching the source line; Delete Line removes the source line. The menu is fully native, so it follows the system appearance in Light and Dark.

Sheets and folders

Work in named sheets with line numbers, syntax tinting and a live results column. Sheets are grouped by the one-level folder tabs pinned to the bottom of the sidebar: the built-in General tab plus any custom folders you create. Selecting a tab filters the sheet list only — your editor and cursor never jump. The main window resizes down to a 260pt content height for compact desks; the default stays 800×600 and the sidebar and answers keep scrolling safely.

Styling and constants

Choose Auto (follow macOS), Light or Dark for the whole app, pick the Dock/App Switcher icon (Dark — the signed bundle icon and the default — or Light), then tune font size, font design and role colors, decimal places, input helpers, line numbers, interface language, the currency display, and an option to hide the sidebar button once collapsed — reopen it any time with ⌃⌘S (Control-Command-S) or View > Toggle Sidebar. Define up to 100 app-wide constants (PI = 3.141592653589793, Sales Tax = 20%, Side = sqrt(4)) that are available in every sheet and resolved live through the same strict engine — function arguments included. See docs/SETTINGS_AND_APPEARANCE.md for the full settings reference: icon-over-label tiles across the top of the window (General, Editing, Numbers, Constants & Units, Styling, About) with one focused page each — language, appearance and the application icon live together in General, and About carries the app identity plus the update controls.

First launch

A genuinely new install opens on a short, native calculation bloom: ten real calculations in the app's own editor palette stream into two airy columns around the app icon, gather into it and disappear, and the icon answers with a one-shot silver splash (fine monochrome rays, a soft expanding wave and a few droplets). The splash settles into a compact final lockup: the icon grows from its streaming footprint to a large 152 pt frame, the official slogan Think freely. We’ll do the math. fades in beneath it in the same neutral tone, and a single monochrome Get Started button — silver on Dark, graphite on Light, matching the icon rather than the accent colour — appears last. The slogan itself is a two-line monochrome lockup (a rounded clause answered by an italic serif, then a quieter rounded line answered by a compact monospaced one), revealed as one calm block. The whole sequence runs once for roughly two and a half seconds and stops; with **Reduce Motion** the large icon, slogan and button are simply there, immediately usable, with no staged animation at all.

Pressing Get Started records a small versioned marker (welcome-v1) in the app's data directory (separate from your settings and sheets), mounts the notebook underneath and then slides the welcome panel up out of the content bounds like a curtain over 0.75 s — the window itself never moves, resizes or loses its titlebar. The notebook, its sidebar and TextKit are not created behind the welcome, and focus lands in the editor only after the curtain has cleared.

Existing installs never see the bloom: any prior artifact — the store (even corrupt or unreadable), the currency-rate cache, the weather cache or the location cache — counts as an existing install, and in that case the completion marker is recorded best-effort without touching those files. Closing the window before pressing Get Started leaves no marker, so the bloom returns next launch. Your Light/Dark/Auto choice and app icon are never changed by any of this.

Files and storage

Sheets persist locally in Application Support. The only network traffic is the background rates refresh plus Open-Meteo lookups for weather in … lines you type yourself — never GPS or location data. From the File menu, import or export any sheet as a .nlx file, export it as a PDF, or print it (⌘P) — export and print are offline and never touch the live editor. Drag a sheet onto a folder tab to re-file it. See docs/EXPORT_AND_PRINT.md.

Download

• macOS 26 or later, Apple Silicon (arm64).
• 4.8.2 is the current release. 4.8.0 was the first release with secure in-app

• Download the .dmg from the latest release,

• Numlex is ad-hoc signed and not notarized. On first launch, Control-click (or

• Verify your download with the checksums file from the same release:

shasum -a 256 -c SHA256SUMS

Homebrew

You can also install Numlex from the project's own custom tap:

brew install --cask Qulierm/tap/numlex

This uses the project's custom Qulierm/tap, not the official Homebrew cask repo. Numlex is ad-hoc signed and not notarized, so on first launch you still have to Control-click (or right-click) Numlex.app, choose Open, and confirm the prompt.

Build from source

Requires macOS 26 with the Swift 6.2 toolchain; Xcode Command Line Tools are enough (xcode-select --install).

swift build               # debug
swift build -c release    # release

The engine suite covers 1,248 shared cases, runnable two ways:

swift test                # Swift Testing suite (full Xcode toolchain)
swift run NumlexTests     # standalone runner (Command Line Tools only)

Package a signed app bundle:

Scripts/build-app.sh [debug|release]   # produces .build/Numlex.app

License

Numlex is available under the MIT License.