LET function

This function assigns a name with the value_expression results and returns the result of the formula_expression.

Sample Usage

LET(avg, AVERAGE(B2:D2), IF(avg>=4, "Great", IF(avg>=3, "Good", "Poor"))): Categorize an average value.

LET(criteria, "Fred", range, FILTER(A2:D8, A2:A8=criteria), ARRAYFORMULA(IF(ISBLANK(range), "-", range))): Filter data and replace blank cell with dash.

Syntax

LET(name1, value_expression1, [name2, …], [value_expression2, …], formula_expression )

  • name1: A name used inside the next value_expressions and the formula_expression. This must be an identifier (details below), and usage is case-insensitive.
  • value_expression1: Formula whose result can be referred to later with the name that was declared before. It can use names declared in the previous parameters.
    • For example, AVERAGE(B2:D2).
  • name2…: [ OPTIONAL ] Repeatable, additional names to be assigned.
  • value_expression2…: [ OPTIONAL ] Repeatable, additional value_expressions to be evaluated.
  • formula_expression: Formula to be calculated. It uses names declared in the LET function.

Tip: You can use formula_expression as the names defined in the scope of the LET function. The value_expressions evaluates only once in the LET function, even if the next value_expressions or the formula_expression uses them multiple times.

Examples

Categorize the average value of product ratings with LET

Example Data:

 

A

B

C

D

1

Product

January ratings

February ratings

March ratings

2

Red t-shirt

3.5

4

3

3

Black jeans

4.5

5

3.5

4

Hat

3

2.5

2

With LET: Input this formula in E2 and drag the blue box around the cell down to fill E3 and E4.

=LET(avg, AVERAGE(B2:D2), IF(avg>=4, "Great", IF(avg>=3, "Good", "Poor")))

Without LET: Input this formula in E2 and drag the blue box around the cell down to fill E3 and E4.

=IF(AVERAGE(B2:D2)>=4, "Great", IF(AVERAGE(B2:D2)>=3, "Good", "Poor"))

Result:

 

A

B

C

D

E

1

Product

January ratings

February ratings

March ratings

Average Rating Category

2

Red t-shirt

3.5

4

3

Good

3

Black jeans

4.5

5

3.5

Great

4

Hat

3

2.5

2

Poor

Make a Copy

Filter data & replace blank cell with dash using LET

Return all data for “Fred” and replace blank cells with dash.

Example Data:

 

A

B

C

D

1

Rep

Region

Product

Profit

2

Amy

East

Apple

$1.33

3

Fred

South

Banana

$0.09

4

Amy

West

Mango

$1.85

5

Fred

North

 

$0.82

6

Fred

West

Banana

$1.25

7

Amy

East

Apple

$0.72

8

Fred

North

Mango

$0.54

With LET: Input this formula in E2:

=LET(criteria, "Fred", range, FILTER(A2:D8, A2:A8=criteria), ARRAYFORMULA(IF(ISBLANK(range), "-", range)))

Without LET: Input this formula in E2:

=ARRAYFORMULA(IF(ISBLANK(FILTER(A2:D8, A2:A8="Fred")), "-", FILTER(A2:D8, A2:A8="Fred")))

Result:

 

E

F

G

H

1

Rep

Region

Product

Profit

2

Fred

South

Banana

0.09

3

Fred

North

-

0.82

4

Fred

West

Banana

1.25

5

Fred

North

Mango

0.54

Make a Copy

Common Errors

The name argument isn’t an identifier

Example: =LET(B2, AVERAGE(B2:D2), IF(B2>=4, "Great", IF(B2>=3, "Good", "Poor")))

If the argument isn’t an identifier, this error occurs:

Identifier requirements:

  • Can’t be ranges, like “A1” or “A2”
  • Can’t have spaces or special characters
  • Can’t start with numbers, like “9hello”
Left-to-right scoping problem

In a value_expression inside the LET function, this syntax lets you use the named arguments which have already been declared earlier. For example, “left in the function.”

Example:

LET(x, 1, y, LET(z, 2, x+z), x+y)

CORRECT — x has been declared before using it in the inner LET function.

LET(y, LET(z, 2, x+y), x, 1, x+y)

WRONG — using x before its declaration.

If you use an argument before it’s declared, this error occurs:

Related functions

true
Visit the Learning Center

Using Google products, like Google Docs, at work or school? Try powerful tips, tutorials, and templates. Learn to work on Office files without installing Office, create dynamic project plans and team calendars, auto-organize your inbox, and more.

Search
Clear search
Close search
Google apps
Main menu
12852820639442610183
true
Search Help Center
true
true
true
true
true
35