Number & String Operations

Custom Variable Template for Server-Side Google Tag Manager

Set of Math and string manipulation operations

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Change Notes

2025/05/28

New boolean operations (placed in the "calc" section): AND, OR, NOT Results of "string" operations can be parsed to integer or fixed Results of the new boolean operations can be parsed (converted) to an integer "0" or "1"

2024/05/25

New string methods "JSON.parse" & "JSON.stringify" for converting from / to objects

2022/06/23

New string method "split+extract": splits string at first parameter by second parameter delimiter and gets array item from split result by third parameter index

New result conversion type "Convert To String"

2021/12/30

New methods in "Math":

• pow
• sqrt

New methods for strings:

• toFixed (variable decimals)
• toNumber (removes thousand separators and converts values with comma as decimal separators)
• replaceAll
• allows empty values as parameter 3 for replace / replaceAll

What it does

Create a new variable using this template to...

• perform calculations with two variables
• use methods from "Math" to mutate variable values or
• manipulate strings from a single input variable (and additional parameters, depending on the string function)

Usage

After selecting one of the three types an operation / a function can be picked from a drop down list.

Depending on the operation, one up to three parameter values can be defined.

• For calculations, the first and second parameter are used as operands. You can use variables or direct constant values for all parameter fields.
• Math and string operations usually take the first parameter as input and the others are used as neccessary function parameters.

All parameters are transformed to the suitable format by the template.

Formatting Results

In case of calculations or math operations you can pick a desired format for the result. This can be a string, rounded or truncated integer or a fixed value with two decimal digits.

Examples

Type	Operation / Function	Parameter 1	Parameter 2	Parameter 3	JavaScript Equivalent	Result
Calculate	add	2	5.5	-unused-	2 + 5.5	7.5
Calculate	subtract	5.5	2	-unused-	5.5 - 2	3.5
Calculate	multiply	2	5.5	-unused-	2 * 5.5	11
Calculate	divide	10	2	-unused-	10 / 2	5
Calculate	AND (Boolean)	true1	false1	-unused-	true && false	false
Calculate	OR (Boolean)	true1	false1	-unused-	true
Calculate	NOT (Boolean)	true1	-unused-	-unused-	!true	false
Math Methods	abs	-42.6	-unused-	-unused-	Math.abs(-42.6)	42.6
Math Methods	ceil	42.6	-unused-	-unused-	Math.ceil(42.6)	43
Math Methods	floor	42.6	-unused-	-unused-	Math.floor(42.6)	42
Math Methods	max	42.6	50	-unused-	Math.max(42.6, 50)	50
Math Methods	min	42.6	2	-unused-	Math.min(42.6, 2)	2
Math Methods	round	42.6	-unused-	-unused-	Math.round(42.6)	43
Math Methods	trunc	42.6	-unused-	-unused-	Math.floor(42.6)	42
Math Methods	pow	2	3	-unused-	Math.pow(2, 3)	8
Math Methods	sqrt	9	-unused-	-unused-	Math.sqrt(9)	3
String Functions	indexOf	Frodo	o	-unused-	"Frodo".indexOf('o')	2
String Functions	lastIndexOf	Frodo	o	-unused-	"Frodo".lastIndexOf('o')	4
String Functions	split	first,second,third	,	-unused-	"first,second,third".split(',')	["first", "second", "third"]
String Functions	splitSpecial	first,second,third	,	1	"first,second,third".split(',')[1]	"second"
String Functions	toLowerCase	Frodo	-unused-	-unused-	"Frodo".toLowerCase()	"frodo"
String Functions	toUpperCase	Frodo	-unused-	-unused-	"Frodo".toUpperCase()	"FRODO"
String Functions	replace	Frodo	o	a	"Frodo".replace('o', 'a')	"Frado"
String Functions	replaceAll	Frodo	o	a	replaceAll("Frodo", 'o', 'a')	"Frada"
String Functions	slice	Frodo	1	3	"Frodo".slice(1, 3)	"ro"
String Functions	substr	Frodo	2	3	"Frodo".substring(2, 5)	"odo"
String Functions	substring	Frodo	2	3	"Frodo".substring(2, 3)	"o"
String Functions	toFixed	3.14159	2	-unused-	(3.14159).toFixed(2)	3.14
String Functions	toNumber	1,234.56	-unused-	-unused-	+(1,234.56)	1234.56
String Functions	match	Frodo	/o/	-unused-	"Frodo".match(/o/)	["o"]
String Functions	sha256	Hello, World!	-unused-	-unused-	sha256Sync("Hello, World!")	"dffd6021bb2bd5b0af676290809ec3a53191dd81c7f70a4b28688a362182986f"
String Functions	base64	Hello, World!	-unused-	-unused-	toBase64("Hello, World!")	"SGVsbG8sIFdvcmxkIQ=="
String Functions	jstringify	{name: "Frodo", age: 50}	-unused-	-unused-	JSON.stringify({name: "Frodo", age: 50})	'{"name":"Frodo","age":50}'
String Functions	jparse	'{"name":"Frodo","age":50}'	-unused-	-unused-	JSON.parse('{"name":"Frodo","age":50}')	{name: "Frodo", age: 50}

Footnotes

1. true, "true", "TRUE", "1", or 1 will be interpreted as true ↩ ↩² ↩³ ↩⁴ ↩⁵