Looker Studio Function : MONTH
Category: DATE function
The Month Function extracts the month (1–12) from a date, enabling efficient month-based calculations and analysis. It’s ideal for summarizing trends, segmenting customers, and supporting data-driven decisions, making reporting more insightful and actionable.d segmentation.
Purpose of the MONTH Function
1. Data Distribution Analysis :
By extracting months, you can analyze monthly trends, visualize peak periods, and understand seasonality—crucial for resource planning, inventory, or campaign effectiveness in a 12‑point timeframe.
2. Customer Segmentation :
Segment customers by month of first purchase, registration, or activity. This enables targeted promotions, onboarding flows, or re-engagement campaigns based on monthly cohort behavior.
3. Decision Making :
Monthly breakdowns help executives identify key patterns or anomalies, enabling timely, data-anchored decisions—such as launching holiday campaigns or adjusting pricing strategies.
Type of Calculation & Practical Use Cases
✅ Performance Benchmarking
Compare monthly sales across regions to set realistic targets.
✅ Customer Segmentation
Group users by signup month to tailor onboarding and marketing.
✅ Time Series Analysis
Visualize monthly trends in web traffic or customer churn.e
MONTH(date_field)
| Parameter | Type | Description |
|---|---|---|
MONTH(date_field) | Date | Accepts a date/timestamp column and returns an integer (1–12). |
How Does the MONTH Function Work?
The function scans each date value in the specified column, extracts the month component, and returns an integer (1 = January, 12 = December). It executes within Looker Studio’s data processing layer during query evaluation.
When to Use It:
Use when you need month-based aggregations, filters, or groupings—like monthly sales reports, seasonality insights, or month-over-month trend comparisons.
Example of MONTH with Result
MONTH(OrderDate)
| OrderDate | Month |
|---|---|
| 2025‑01‑15 | 1 |
| 2025‑03‑22 | 3 |
| 2025‑12‑05 | 12 |
Basic Usage vs. Column Usage
Basic Usage: Apply directly in metrics, e.g.,
MONTH(date)for charts or filters.Column Usage: Create a new dimension “Month” for grouping data in tables or pivot charts.
Example 3: Handling Decimals and Scientific Notation
Since Month returns an integer 1–12, decimal or scientific notation isn’t applicable. However, ensure your date field is properly formatted to avoid conversion issues—use CAST() or format corrections if needed.
Example 4: Combining with Other Functions
CONCAT(CAST(MONTH(date) AS STRING), "-", YEAR(date))→ “3-2025”CASE WHEN MONTH(date) IN (11,12) THEN "Holiday Season" ELSE "Regular" ENDDATETIME_DIFF(DATE_TRUNC(date, MONTH), date, MONTH)for finding month intervals
Tips and Tricks
Always pair
MONTH()withYEAR()to avoid merging values across years.Combine with
DATE_TRUNC(date, MONTH)for consistent first-of-month grouping.Use extraction in filters: e.g.,
MONTH(date) = 1to isolate January data.
The MONTH() function accepts date or datetime fields. If your data is in string format, you must convert it using functions like PARSE_DATE() or CAST() before applying the Month function.
No, MONTH() only returns the numeric month (1–12). To differentiate between years, combine it with the YEAR() function to ensure your analysis doesn’t mix data from different calendar years.
The MONTH() function does not adjust for time zones. It uses the raw date or timestamp as provided, so ensure your data is standardized to a consistent time zone before applying the function.
Yes, if the input field is null or not a valid date format, MONTH() will return null. Make sure your data is clean and date values are properly formatted to avoid this issue.
Absolutely. DATETIME_ADD is frequently used in filters and custom fields to create dynamic date ranges, forecast windows, and time-based segments for better analysis and reporting.