📊 SUM Function: The Basic Formula for Calculating Totals in Google Sheets

🔍 What is the SUM function?

The SUM function is one of the most essential and fundamental functions in Google Sheets.
It allows you to calculate the total of selected numeric cells quickly and efficiently.

For example, if you want to add up the values from A1 to A5, simply enter:

=SUM(A1:A5)

It works exactly like in Excel, making it very familiar for spreadsheet users.

🧪 Basic Syntax

=SUM(number1, [number2, ...])

• Each argument can be a number, a cell reference, a range, or a combination.
• You can mix ranges and specific values.

📌 Example 1: Adding a single range

=SUM(A1:A3)

👉 Result: 60
👉 Empty or text cells are ignored.

📌 Example 2: Summing multiple ranges

=SUM(A1:A3, B1:B3)

👉 Result: 105
👉 Explanation: 60 (from A1:A3) + 45 (from B1:B3)

📌 Example 3: Mixing values and ranges

=SUM(10, 20, 30, A1:A3)

Assuming A1:A3 = 1, 2, 3
👉 Result: 10 + 20 + 30 + 1 + 2 + 3 = 66

📌 Example 4: Using SUM with conditions (no SUMIF)

You can use FILTER to dynamically sum only values that meet a condition.

=SUM(FILTER(A1:A10, B1:B10="Completed"))

👉 This sums only the A column values where B equals "Completed"
👉 Very useful for status-based reports

💼 Use Case ①: Monthly revenue totals

=SUM(FILTER(B1:B4, TEXT(A1:A4,"yyyy-mm")="2025-07"))

👉 Result: 750000 (only rows from July)

💼 Use Case ②: Summing salaries by department

=SUM(FILTER(C1:C3, B1:B3="Sales"))

👉 Result: 6100000
👉 You can build conditional sums without SUMIF

⚠️ Things to Watch Out For

🧩 Frequently Combined With

✅ Summary

• SUM is the most basic and widely used function in Google Sheets.
• It works with direct values, ranges, and filtered results.
• When combined with functions like FILTER, ARRAYFORMULA, and QUERY,
  it becomes a powerful tool for real-time reporting and automation.