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Formula functions reference

Updated 2026-06-22

This is the complete list of functions and operators Numio evaluates when your calculator runs. The list is finite and exact — anything not on this page is not supported, and any function Numio doesn't recognize quietly evaluates to 0 rather than erroring.

Writing a formula

Every formula starts with =. References are case-insensitive (b1 and B1 are the same), commas separate arguments, and colons denote ranges (D1:D10).

=D1 + D2
=SUM(D1:D10)
=IF(D1 > 100, "Large", "Small")

Operators

| Operator | Meaning | |---|---| | + - * / | Add, subtract, multiply, divide | | ^ | Power (2^3 = 8) | | % | Postfix percent — divides by 100 (50% = 0.5). This is not modulo | | = <> < > <= >= | Comparisons (return 1 for true, 0 for false) |

TRUE and FALSE are recognized and evaluate to 1 and 0.

Math and rounding

| Function | What it does | Example | |---|---|---| | SUM | Adds all values in the arguments/ranges | =SUM(D1:D5) | | AVERAGE / AVG | Mean of the values | =AVERAGE(D1:D5) | | MIN / MAX | Smallest / largest value | =MAX(D1:D5) | | COUNT | Count of numeric values | =COUNT(D1:D5) | | ROUND | Round to N decimal places (default 0) | =ROUND(D1, 2) | | ROUNDUP | Round up to N decimal places | =ROUNDUP(D1, 2) | | ROUNDDOWN | Round down to N decimal places | =ROUNDDOWN(D1, 2) | | CEILING | Round up to the nearest integer | =CEILING(D1) | | FLOOR | Round down to the nearest integer | =FLOOR(D1) | | ABS | Absolute value | =ABS(D1) | | SQRT | Square root | =SQRT(D1) | | POWER | Raise to a power | =POWER(D1, 2) |

Logic

| Function | What it does | Example | |---|---|---| | IF | Returns the second argument when the first is truthy, otherwise the third | =IF(D1>100, "High", "Low") | | AND | 1 if every argument is truthy | =AND(D1>0, D2>0) | | OR | 1 if any argument is truthy | =OR(D1>0, D2>0) | | NOT | Inverts a truthy/falsy value | =NOT(D1) | | IFERROR | Returns the second argument if the first is empty or not a finite number | =IFERROR(D1/D2, 0) |

Lookup

| Function | What it does | Example | |---|---|---| | VLOOKUP | Find a row by its first-column value, return another column. Exact match with FALSE; approximate (ascending) otherwise | =VLOOKUP(D1, G1:H20, 2, FALSE) | | HLOOKUP | Like VLOOKUP but searches the first row and returns from a row index | =HLOOKUP(D1, G1:J3, 2, FALSE) | | INDEX | Return the value at a row (and optional column) of a range | =INDEX(G1:H10, 3, 2) | | MATCH | Position of a value within a range | =MATCH(D1, G1:G10, 0) |

INDEX + MATCH combine for flexible lookups:

=INDEX(H1:H10, MATCH(D1, G1:G10, 0))

How errors are handled

Numio's evaluator never shows a #REF! or #DIV/0! code to your reader. Instead:

  • Unknown functions evaluate to 0. If you type a function not listed above, it silently returns 0.
  • Division by zero returns 0 rather than infinity or an error.
  • Empty or non-numeric cells count as 0 in arithmetic.

There is no MOD function and no text functions (no CONCAT, LEFT, TEXT, and so on). Stick to the functions on this page.

See Formula verification and errors for how these behaviors play out while you build.

Where to go next