Data Studio function list
Data Studio provides a number of powerful functions that can be used inside of calculated field formulas.
More information on each function, including examples, is available in the formula editor. This help will appear as you begin to type your formula.
Type  Name  Description  Syntax 

Aggregation  AVG  Returns the average of all values of X. 
AVG(X)

Aggregation  COUNT  Returns the number of values of X. 
COUNT(X)

Aggregation  COUNT_DISTINCT  Returns the number of unique values of X. 
COUNT_DISTINCT(X)

Aggregation  MAX  Returns the maximum value of X. 
MAX(X)

Aggregation  MEDIAN  Returns the median of all values of X.  MEDIAN(X) 
Aggregation  MIN  Returns the minimum value of X. 
MIN(X)

Aggregation  PERCENTILE  Returns the percentile rank Y of field X.  PERCENTILE(X,Y) 
Aggregation  SUM  Returns the sum of all values of X. 
SUM(X)

Aggregation  VARIANCE  Returns the variance of X.  VARIANCE(X) 
Arithmetic  ABS  Returns the absolute value of number. 
ABS(X)

Arithmetic  ACOS  Returns the inverse hyperbolic cosine of X. 
ACOS(X)

Arithmetic  ASIN  Returns the inverse hyperbolic sine of X. 
ASIN(X)

Arithmetic  ATAN  Returns the inverse hyperbolic tangent of X. 
ATAN(X)

Arithmetic  CEIL  Returns the smallest integral value of X. For example, if the value of X is v, CEIL(X) is greater than or equal to v. 
CEIL(X)

Arithmetic  COS  Returns the cosine of X. 
COS(X)

Arithmetic  FLOOR  Returns the largest integral value of X. For example, if the value X is v, FLOOR(X) is equal to or less than v. 
FLOOR(X)

Arithmetic  LOG  Returns the natural logarithm of X. 
LOG(X)

Arithmetic  LOG10  Returns the logarithm to base 10 of X. 
LOG10(X)

Arithmetic  NARY_MAX  Returns the maximum value of X, Y, [,Z]*. All input arguments must be of the same type: all numbers or all text. At least one input argument must be a field or an expression containing a field. 
NARY_MAX(X, Y, [Z]*)

Arithmetic  NARY_MIN  Returns the minimum value of X, Y, [,Z]*. All input arguments must be of the same type, all numbers or all text. At least one input argument must be a field or an expression containing a field. 
NARY_MIN(X, Y, [Z]*)

Arithmetic  ROUND  Returns X rounded to Y precision digits. 
ROUND(X, Y)

Arithmetic  SIN  Returns the sine of X. 
SIN(X)

Arithmetic  SQRT  Returns the square root of X. Note that X must be nonnegative. 
SQRT(X)

Arithmetic  TAN  Returns the tangent of X. 
TAN(X)

Date  DATE_DIFF  Returns the difference in days between X and Y (X  Y). 
DATE_DIFF(X, Y)

Date  DAY  Returns the day of X. 
DAY(X, Input Format)

Date  HOUR  Returns the hours in X in UTC timezone. 
HOUR(X, Input Format)

Date  MINUTE  Returns the minutes in X in UTC timezone. 
MINUTE(X, Input Format)

Date  MONTH  Returns the month in X. 
MONTH(X, Input Format)

Date  QUARTER  Returns the quarter of X. 
QUARTER(X, Input Format)

Date  SECOND  Returns the seconds in X in UTC timezone. 
SECOND(X, Input Format)

Date  TODATE  Returns the datetime field in the specified format in UTC. 
TODATE(X, Input Format, Output Format)

Date  WEEK  Returns the week of X from start of year as per ISO 8601 standard.  WEEK(X) 
Date  WEEKDAY  Returns the day of the week of X. 
WEEKDAY(X, Input Format)

Date  YEAR  Returns the year of X. 
YEAR(X, Input Format)

Date  YEARWEEK  Returns the year and week of X as per ISO 8601 standard.  YEARWEEK(X) 
Geo  TOCITY  Returns the city name for X. 
TOCITY(X, Input Format)

Geo  TOCONTINENT  Returns the continent name for X. 
TOCONTINENT(X, Input Format)

Geo  TOCOUNTRY  Returns the country name for X. 
TOCOUNTRY(X, Input Format)

Geo  TOREGION  Returns the region name for X. 
TOREGION(X, Input Format)

Geo  TOSUBCONTINENT  Returns the subcontinent name for X. 
TOSUBCONTINENT(X, Input Format)

Miscellaneous  CASE  Evaluates to exactly one value based on a set of given boolean expressions. Learn more 

Miscellaneous  CAST  CAST(field_expression AS TYPE)  Cast field or expression into TYPE. Aggregated fields are not allowed inside CAST.TYPE can be NUMBER or TEXT. 
Text  CONCAT  Returns a text that is the concatenation of X and Y. Note that either X or Y must be an expression that has at least one field; the other can be a text literal. Arguments must be either both aggregated or both unaggregated. 
CONCAT(X, Y)

Text  LENGTH  Returns the number of characters in X. 
LENGTH(Field Or Expr)

Text  LOWER  Converts X to lowercase.  LOWER(Field Or Expr) 
Text  REGEXP_EXTRACT  Returns first matching substring in X which matches regex pattern. Learn more  REGEXP_EXTRACT(Field Or Expr, Extract regex pattern) 
Text  REGEXP_MATCH  Returns true if X matches Y, false otherwise.  REGEXP_MATCH(X, Reg Expr) 
Text  REGEXP_REPLACE  Replaces all occurences of text which matches the regex in X with the replacement string.  REGEXP_REPLACE(A, '[az]+', 'A') 
Text  REPLACE  Returns a copy of X with all occurrences of Y in X replaced by Z. 
REPLACE(Field Or Expr, Existing Literal, Replacement Literal)

Text  SUBSTR  Returns a text that is subtext of X. The subtext consists of X[Y], X[Y+1], ..., X[Y+Z1]. 
SUBSTR(Field Or Expr, Start Index, Length)

Text  TRIM  Returns X with leading and trailing whitespace removed. 
TRIM(Field Or Expr)

Text  UPPER  Converts X to uppercase.  UPPER(Field Or Expr) 
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