Looker Studio Function : DATETIME_ADD
Category: Arithmetic function
The DATETIME_ADD function in Looker Studio is used to add a specified time interval (such as days, months, or years) to a datetime value. It is essential for time-based data manipulation, enabling advanced temporal analysis, forecasting, and segmentation.
Purpose of the DATETIME_ADD Function
1. Data Distribution Analysis :
The function helps analyze how data points spread across different time periods. By adjusting datetime values, users can uncover temporal trends, seasonal patterns, and peak activity windows.
2. Customer Segmentation :
It enables dynamic grouping of customers based on their behavior over time. For instance, you can segment users who made purchases within 7 days of signup using this function.
3. Decision Making :
Business decisions often depend on timely insights. DATETIME_ADD allows analysts to model future events, predict performance, and schedule campaigns based on time-shifted data.
Type of Calculation & Practical Use Cases
✅ Performance Benchmarking
Compare current metrics with past or projected periods by shifting timeframes using DATETIME_ADD.
✅ Customer Segmentation
Group users by time-based behavior, such as login activity after registration or churn periods.
✅ Time Series Analysis
Analyze changes in metrics over uniform time intervals, improving trend analysis accuracy.
DATETIME_ADD(datetime_expression, INTERVAL int64_expression date_part)
| Parameter | Type | Description |
|---|---|---|
datetime_expression | DATETIME | The original datetime value to modify. |
int64_expression | INTEGER | The number of units to add. |
date_part | STRING | The type of time unit (e.g., DAY, WEEK, MONTH, YEAR). |
How Does the DATETIME_ADD Function Work?
The DATETIME_ADD function adds a specified time interval to a given datetime. It operates by evaluating the datetime expression, identifying the interval, and outputting a new datetime value. It runs when a calculated field or metric using this function is called in your report.
When Should You Use DATETIME_ADD Function?
Use DATETIME_ADD when you need to shift time periods for comparative analysis, forecast modeling, or date-based filtering. It’s perfect for dynamic dashboards requiring rolling windows or future/past projections.
Example of DATETIME_ADD with Result
DATETIME_ADD(DATETIME “2025-06-01 00:00:00”, INTERVAL 10 DAY)
Result : 2025-06-11 00:00:00
Example : 1 Basic Usage
Apply in calculated fields to shift datetime values for metrics like “Revenue 7 Days After Signup.”
Example 2: Column Usage
Use DATETIME_ADD to create derived columns such as “Order Follow-Up Date” or “Subscription Renewal Date.”
Example 3: Handling Decimals and Scientific Notation
The interval must be an integer. To use decimals, round or cast values before applying DATETIME_ADD. Scientific notation isn’t supported directly.
Example 4: Combining with Other Functions
DATETIME_ADD works well with:
TODAY()for dynamic comparisonsIF()for conditional logicDATE_DIFF()for comparative duration analysis
Tips and Tricks
Use
DATETIME_ADDwith filters to create rolling time windows.Combine with
TODAY()for real-time dashboards.Use negative values for backward time shifts.
Yes, you can use negative integers with DATETIME_ADD to subtract time from a datetime value, allowing for flexible time-based calculations such as comparing past events or creating rolling time windows.
DATETIME_ADD supports standard time units like SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, and YEAR, making it versatile for most temporal calculations in Looker Studio reports and custom fields.
Yes, chaining is possible by nesting DATETIME_ADD functions, but it’s usually better to calculate the total interval first to keep your formulas clean, simple, and easier to maintain.
No, DATETIME_ADD only works with DATETIME values. For DATE fields, use DATE_ADD. Always match your function to the field type to avoid errors.
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.