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A/B Copy Variant Generator

Generate two properly structured A/B variants with single-variable testing — free, no sign-up.

The golden rule of A/B testing copy

Most marketers run invalid A/B tests without knowing it. If Variant A and Variant B differ in three ways, you'll never know which change caused the result. The single-variable principle is non-negotiable: change one thing, measure one thing.

Test one variable

Change only the headline angle, CTA, or value prop — not all three at once.

Keep everything else identical

Same offer, same layout, same audience, same traffic source.

Set a hypothesis first

"If Variant B wins, it means our audience responds more to urgency than curiosity."

Wait for significance

100+ conversions per variant minimum. Don't call a winner at 12 clicks.

Test your highest-traffic element first

Headlines and CTAs move the needle most. That's where to start.

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