toFixed — GTM Variable Template for Number

VARIABLES › NUMBER

toFixed CORE Number

Direct (.tpl) Apply (.tpl) Add to GTM

Rounds a number to a fixed number of decimal places.

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When to Use This

Formatting

Normalize casing, spacing, encoding, and presentation of data values.

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Examples

Round to 2 decimals▶ Try

INPUT

Number To Round: 3.14159
Decimal Places: 2

OUTPUT

3.14

Trailing zeros added▶ Try

INPUT

Number To Round: 10.5
Decimal Places: 3

OUTPUT

10.500

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Live Sandbox

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toFixed

Read-Only Try Live

Number To Round

💾 The number to round to fixed decimal places.

Supported formats:
  ✓ Number
  ✓ String

Decimal Places

🎯 Number of decimal places to keep.

Supported formats:
  ✓ Number
  ✓ String

Input Setup

Input Function (optional)

⚙️ Optional pre-processing function applied to the input before internal logic (e.g., convert object to string, normalize case). Internal transformations such as case handling will still apply afterward.

Result Handling

Output Function (optional)

⚙️ Optional function to apply to the result before returning it (e.g., str => str + ' €', val => val !== undefined for boolean conversion). Useful for chaining transformations on the output.

Number To Round number

💡 Type any text to see the result update live

🎯 Using special value — click input to type instead

Test with:

Falsy undefined null "" empty 0 false NaN

Truthy true 42 "hello" {} empty [] empty {a:1} [1,2,3]

Decimal Places number

🔗 Result Handling — Chain Variables

Chain apply-mode variables to the output. Each variable receives the result of the previous one.

toFixed()

+ Chain another variable

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Related Variables

Same category: Number

→ absolute → addValues → calculateDiffRatio → ceil → clamp → classifyByThreshold → countDigits → divide → floor → max → min → multiply → parseCurrency → parseFloatValue → parseIntValue → percentOf → scaleToRange → squareRoot → subtractValues → toFixedNumber → toInteger → 🧩 WEIGHTED (Advanced) → 🧩 WEIGHTED (Predefined)

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Under the Hood

📜 View Implementation Code

/**
* Rounds a number to a fixed number of decimal places using Math.round.
*
* @param {number} data.src - The number to round.
* @param {number|string} data.dec - Number of decimal places to keep.
* @param {Function|string} [data.out] - Optional output handler: function to transform result or string with format.
*
* Direct-mode specific parameters:
* @param {Function} [data.pre] - Optional pre-processor function to transform src before rounding.
*
* @returns {string} The rounded number as a string with fixed decimals.
*
* @framework ggLowCodeGTMKit
*/
const Math = require('Math');
const makeNumber = require('makeNumber');

const toFixed = function(num, decimals) {
   const numValue = makeNumber(num);
   const decValue = makeNumber(decimals);
   const factor = Math.pow(10, decValue);
   const rounded = Math.round(numValue * factor) / factor;
   const parts = rounded.toString().split('.');
   const integerPart = parts[0];
   let decimalPart = parts[1] || '';
   while (decimalPart.length < decValue) {
       decimalPart += '0';
   }
   if (decValue === 0) {
       return integerPart;
   }
   return integerPart + '.' + decimalPart;
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// toFixed - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(toFixed(value, data.dec));
// ===============================================================================
// toFixed(...) – Apply Mode
// ===============================================================================
/*
return function(value, decimals) {
   decimals = data.rp1 ? decimals : data.dec;
   return out(toFixed(value, decimals));
};
*/

🧪 View Test Scenarios (5 tests)

✅ '[example] Round to 2 decimals'
✅ Valid number with 0 decimal places - returns integer
✅ '[example] Trailing zeros added'
✅ String number with decimal places - converts and rounds
✅ Integer with decimal places - adds decimal point and zeros