Math & Trig

RAND Function in Excel

Returns a random decimal number between 0 and 1.

Syntax

  • =RAND()

Examples

  • =RAND() - Random decimal 0-1 - Result: 0.xxxxx
  • =RAND()*100 - Random number 0-100 - Result: Random value

Excel RAND function documentation

  • RAND returns a random decimal greater than or equal to 0 and less than 1.
  • Syntax: =RAND(). No arguments. Volatile — recalculates on every worksheet change.
  • Use for simulations, random samples, lottery draws, and shuffling with helper columns.
  • Related: [RANDBETWEEN](/functions/randbetween/), [RANDARRAY](/functions/randarray/), [SORT](/functions/sort/).

RAND syntax and volatile behavior

  • Each recalculation produces new values — freeze with Paste Special → Values.
  • Scale to range: =RAND()*(max-min)+min for continuous random between bounds.
  • Never use RAND alone for cryptographic security — not cryptographically random.
  • Many RAND cells slow huge models — limit count or switch to RANDARRAY block.

Step-by-step: random 10% audit sample

  • Step 1 — Data rows 2:1000.
  • Step 2 — Helper column: =RAND() copied down.
  • Step 3 — Filter rows where helper <= 0.1 for ~10% sample.
  • Step 4 — Paste values on helper before sharing workbook.
  • Step 5 — For integer IDs use [RANDBETWEEN](/functions/randbetween/) instead.

RAND vs RANDBETWEEN vs RANDARRAY

  • RAND — decimal 0–1; scale manually.
  • RANDBETWEEN — integer inclusive range.
  • RANDARRAY — spill grid of random values in Microsoft 365.
  • Shuffle list: helper RAND + Sort ascending on helper.

Worked examples to copy

  • Random percent: =RAND().
  • 0–100 score: =RAND()*100.
  • Random yes/no: =IF(RAND()>0.5,"Yes","No").
  • Unique random order: =RAND() then Data → Sort.

People also ask

  • Stop RAND from changing? — Copy → Paste Special → Values.
  • RAND integer 1–6? — Use =RANDBETWEEN(1,6).
  • RAND same seed? — Excel has no built-in seed; use RANDARRAY or VBA for reproducible runs.
  • RAND slow workbook? — Volatile; replace with static values after generation.

Common errors

  • Recalculates on every worksheet change

Use cases

  • Random sampling
  • Simulations
  • Test data generation

Frequently asked questions

  • How do I generate a random number that doesn't change? RAND recalculates on every change. To freeze random values: 1) Select cells with RAND formulas, 2) Copy (Ctrl+C), 3) Paste Special > Values (Ctrl+Shift+V). This replaces formulas with static numbers.
  • How do I generate random numbers in a specific range? Use =RAND()*(max-min)+min. For random between 50 and 100: =RAND()*50+50. For integers, wrap in INT or ROUND: =INT(RAND()*51+50). Or use RANDBETWEEN(50,100) for integers directly.
  • Is RAND truly random? RAND uses a pseudorandom number generator - it's statistically random enough for most purposes but not cryptographically secure. For simulations and sampling it's excellent. For security-critical applications, use external tools.

Editorial review

  • Reviewed by Excel.Directory Editorial Team. Updated May 2026.

When to use RAND

  • Random sampling — common Math & Trig scenario for RAND.
  • Simulations — common Math & Trig scenario for RAND.
  • Test data generation — common Math & Trig scenario for RAND.

RAND in the Math & Trig category

  • Browse all Math & Trig functions at /categories/math-trig/ for related formulas.
  • RAND syntax: =RAND()
  • Confirm RAND arguments match the syntax shown above before filling down.
  • Lock table and range references with $ when copying formulas across rows or sheets.

Formula checklist before you copy down

  • Confirm RAND arguments match the syntax shown above before filling down.
  • Lock table and range references with $ when copying formulas across rows or sheets.
  • If results look wrong, check for text stored as numbers and invisible spaces with TRIM.
  • Spot-check three known input rows manually against expected output.

Related Excel functions

  • RANDBETWEEN (/functions/randbetween/): Returns a random integer between two specified numbers.
  • RANDARRAY (/functions/randarray/): Returns an array of random numbers.

Errors to watch for

  • Recalculates on every worksheet change — review causes on linked error pages in the directory.

Copy-paste audit workflow

  • Enter RAND on three test rows with known expected output documented on a QA tab.
  • Fill down only after absolute references are locked on lookup tables and rate tables.
  • Compare against manual calculation or a calculator for financial and statistical functions.
  • Search this directory for comparison guides when choosing between similar functions in the same category.

RAND worked examples to copy

  • =RAND() — Random decimal 0-1. Expected result: 0.xxxxx.
  • =RAND()*100 — Random number 0-100. Expected result: Random value.

RAND reference summary for crawlers and offline review

  • RAND belongs to the Math & Trig category in Excel. Returns a random decimal number between 0 and 1.
  • Full syntax: =RAND(). Open /functions/rand/ for parameters, FAQs, and related pages.
  • Common mistakes: Recalculates on every worksheet change
  • Pair this function with comparison guides when another Excel formula might fit the same task better.
  • Review fix-excel-formula-errors when unexpected errors appear after upgrading Excel or sharing across locales.