Custom Columns

Custom Columns are user-created metrics in Google Ads that use formulas to combine existing performance data into new calculated fields. They appear alongside standard columns in reporting tables and can incorporate arithmetic operations, conditional logic, and date-range comparisons to surface insights not available in default metrics.

Key Takeaways

• Create custom calculated metrics using formulas on existing Google Ads data
• Appear as regular columns in campaign, ad group, and keyword tables
• Support arithmetic operations, conditional logic, and cross-date-range comparisons
• Up to 36 custom columns per account
• Ideal for agency-specific KPIs, profit calculations, and performance benchmarks

What Are Custom Columns

Custom Columns extend Google Ads reporting beyond its built-in metrics. While Google provides standard columns like CPC, CTR, and Conversions, your business may need metrics like profit margin, blended CPA across conversion types, or week-over-week change percentages. Custom Columns let you build these directly in the interface.

Formula Component	Supported Operations
Arithmetic	+, -, *, / on any numeric metrics
Functions	IF/THEN, MIN, MAX, ABS
Metric references	Any standard Google Ads metric
Constants	Fixed numbers for margins, targets, etc.
Date ranges	Compare current period to previous period

How It Works

Creating a custom column in the 2026 Google Ads interface:

1. Navigate to any reporting table (Campaigns, Ad groups, Keywords)
2. Click the Columns icon and select Modify columns
3. Click Custom columns at the bottom of the panel
4. Click + New column
5. Name the column, write the formula, and set the format (number, percentage, currency)
6. Save and apply — the column appears in your table

Formulas reference existing metrics by name. For example:

• Profit per conversion: Conv. value - Cost (shows profit after ad spend)
• Revenue per click: Conv. value / Clicks
• CPA vs. Target: IF(Cost/Conversions > 50, "Over Target", "On Target")
• Week-over-week cost change: (Cost - Cost (prev. period)) / Cost (prev. period) * 100

Custom columns update in real time as underlying data changes. They can be used with filters to isolate specific performance ranges and included in downloaded reports.

Practical Example

An e-commerce advertiser creates three custom columns:

Custom Column	Formula	Purpose
Gross Profit	Conv. value * 0.35 - Cost	35% product margin minus ad cost
Profit ROAS	(Conv. value * 0.35) / Cost * 100	Return on ad spend based on margin
Efficiency Score	IF(Conversions > 0, (Conv. value * 0.35 - Cost) / Cost * 100, -100)	Profit as percentage of spend

Viewing the Campaigns table with these columns:

Campaign	Cost	Revenue	Gross Profit	Profit ROAS	Efficiency
Running Shoes	$3,000	$15,000	$2,250	175%	75%
Accessories	$2,000	$4,500	-$425	-21%	-21%
Clearance	$1,500	$8,000	$1,300	187%	87%

Standard ROAS shows Accessories at 225% ($4,500/$2,000) — seemingly profitable. But the Gross Profit column reveals it is actually losing $425/month when accounting for product margins. This insight would require spreadsheet analysis without custom columns.

Why It Matters

Custom Columns bring business-specific metrics directly into the Google Ads interface, eliminating the need to export data to spreadsheets for critical calculations. For agencies, custom columns standardize how performance is evaluated across accounts — every team member sees the same calculated metrics. They are particularly valuable for margin-based businesses where standard ROAS is misleading, for accounts with target-based KPIs, and for any advertiser who needs to compare current performance to benchmarks. Combined with segments and filters, custom columns transform the Google Ads interface into a tailored analytics dashboard.