Natural calculations

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

This guide walks through the everyday forms; every one of them is specified in full in the Syntax Reference.

Arithmetic

Standard operators with normal precedence:

30 + 567 × 2        1,164
(30 + 567) × 2      1,194
100 / 8             12.5
2 ^ 10              1,024

Spaces around operators are optional, parentheses group, and ^ is power. The full precedence table — including how if … then … else … fits in — is in Operators & logic.

Percentages

Percentage grammar reads like a note:

15% of 4572         685.8
10% of 240          24
240 + 10%           264

In an additive context a trailing percent applies to the value to its left, so 240 + 10% is 264. All the phrase forms (% off, what %, fractions, multipliers) are in Percentages.

Money and finance

Money uses the same arithmetic, with a currency marker or ISO code. Finance phrases also cover compound interest, loans, tax and inflation:

$240 + 10% tip      $264.00
lunch = $45
2 people × lunch    $90
$1,000 after 3 years at 7%      $1,225.04
monthly repayment on $10,000 over 6 years at 6%   $165.73

The marker table, named values and time rates ($24 per day) are documented in Money & rates; investments, loans, configured sales tax, the 2026 income-tax estimates and CPI inflation are in Finance & investments.

Dates & times

Calendar dates, clocks, timezones, durations and workdays all read as plain lines:

Jan 10 + 12 days    Jan 22
June 12 + 45 days
today
3:30pm + 2 hours    5:45 pm
2am PST to GMT      10:00 am
workdays in 3 weeks 15 workdays

Calendar arithmetic is component-based and DST-safe, timezones resolve through an offline catalog, and work calendars use bundled holiday data. The complete temporal reference — durations, timestamps and ISO 8601, Timespan, video Timecode, work calendars and special dates — is in Dates & times.

Tags and subtotals

A trailing #tag marks a row, an exact --- divider starts a new section, and subtotal / grand total build section sums. Tag aggregates answer questions about tagged rows:

86.40 #food
12.50 #food
total of #food          98.90
subtotal                98.90

The eligibility rules, tag queries, the statistics functions and the dynamic random behavior are in Tags, subtotals & statistics.

Sections and totals

A # heading starts a section, and a standalone total line sums the section’s eligible answers:

# Household
Groceries               86.40
Power bill              42.10
total                   128.50

A previously computed total is not re-counted by the next total line. The exact eligibility rules (money and unit quantities are not summed, for example) are in Sheet language. The Total footer at the bottom of the sheet can be hidden if you prefer a cleaner column.

Where to go deeper

• Sheet language — every line form and the strict versus quiet rules.
• Dates & times — calendar arithmetic, clocks, timezones, timestamps, Timespan, timecode and work calendars.
• Finance & investments — interest, loans, tax and inflation.
• Tags, subtotals & statistics — tagged rows, section subtotals, aggregates and the footer statistic.
• Export & print — PDF export and native printing.
• Numbers & integer bases — literals and 0x/0b/0o.
• Units & quantities — conversions and unit arithmetic.
• Built-in functions — the 27 functions.