The Copysplit Blog

5 Headline Formulas That Actually Convert

Five proven headline formula archetypes that consistently outperform generic headlines by 20-50% in controlled A/B experiments.

A/B Testing Your CTA: Copy, Color & Placement

What to test on your CTA buttons — copy, color, size, placement — and how to measure results and call a winner with confidence.

How AI is Changing Copywriting Forever

How the smartest teams combine human creativity with AI-generated copy variations to test and optimize faster than ever.

Why Your Landing Page Isn't Converting (And How to Fix It)

Five common landing page conversion killers and the quick-win A/B tests that fix each one. Most take under an hour to launch.

Agency A/B Testing: Scaling Across 10+ Sites

The agency workflow for managing copy A/B experiments across a portfolio of 10+ client sites without losing quality or speed.

A/B Test Statistical Significance Explained

How to know — with real confidence — when your A/B test has a genuine winner versus a statistical fluke that will disappear.

How to A/B Test Website Copy Without a Developer

Pixel-based testing tools let marketers launch and analyze copy experiments independently — no engineering queue required.

How to Build a Copy Testing Program That Compounds

Why headline testing produces faster conversion lifts than any other optimization and how to build a repeatable program.

Copy Testing vs A/B Testing: Key Differences

Copy testing and A/B testing overlap but serve different purposes. Learn when each approach fits, with real campaign examples.

The ROI of Copy Optimization: A Data-Backed Case

Copy changes take minutes and can double conversions. Calculate the true ROI of copy optimization with these frameworks.

AI-Powered A/B Testing: Multi-Armed Bandits and ML

How machine learning generates better copy variations, allocates traffic with multi-armed bandits, and finds winners faster.

12 A/B Testing Mistakes That Kill Your Results

Most A/B tests fail because of avoidable setup and analysis mistakes. Here are twelve common offenders and how to fix each.

Copy Testing for E-Commerce: A Complete Guide

How to systematically test product page copy — headlines, CTAs, and descriptions — to measurably increase revenue per visitor.

Best A/B Testing Tools for Copy Optimization

Seven A/B testing tools compared on features, pricing, and what each one actually does best for copy optimization in 2026.

Bayesian vs Frequentist A/B Testing Explained

Bayesian and frequentist testing both work — but they answer different questions. Here is when each approach really matters.

A/B Testing for Beginners: A Step-by-Step Guide

Learn what A/B testing is, why it matters, and how to run your first experiment from scratch — even with zero technical experience.

A/B Testing Examples: 15 Real Experiments

15 real-world A/B testing examples across headlines, CTAs, landing pages, and pricing — with specific results and takeaways you can apply.

Conversion Rate Optimization Checklist (43-Point)

A 43-point CRO checklist covering headlines, copy, CTAs, forms, social proof, trust signals, page speed, and mobile — with testing priorities.

How to Run Your First A/B Test (Without a Developer)

How to run an A/B test from scratch — a step-by-step walkthrough for marketers who have never tested before. Pick what to test, launch, and declare a winner.

Statistical Significance in A/B Testing Explained (Plain English)

Statistical significance in A/B testing sounds complicated. It is not. Here is what it actually means in plain English — and why it matters.

How Long Should You Run an A/B Test? (Sample Size Math)

The answer is not two weeks. Test duration depends on traffic, baseline conversion rate, and the lift you want to detect. Here is the math.

How Many Visitors Do You Need for an A/B Test?

Running an A/B test on a low-traffic page wastes your time. Here is the minimum sample size you need — and the formula for your specific situation.

A/B Testing vs. Multivariate Testing: When to Use Each

Multivariate testing sounds more powerful than A/B. For most teams, it is the wrong tool. Here is when to use each — and when A/B/n wins.

25 High-Converting Headline Formulas (With Examples)

High converting headline formulas from winning A/B tests — 25 patterns across 5 categories, with templates, real examples, and why each one works.