Built on the belief
that data beats instinct.

We are a premium marketing agency named after the man who proved that advertising could be scientific. Everything we do is tested, measured, and improved.

Our Story

The name we chose says everything about how we work.

John Caples was not the most celebrated creative mind of the twentieth century. He was something more valuable: a man who could prove what worked. As Vice President of BBDO, he pioneered the use of split testing, coded responses, and systematic measurement to determine which advertisements actually moved people to act.

His 1927 headline — "They Laughed When I Sat Down at the Piano — But When I Started to Play!" — is still studied today not because it was clever, but because it was tested and it won. It addressed the reader's fear of embarrassment, offered transformation, and drove response at a scale that silenced the doubters.

We named our agency after Caples because his methods are our methods. We do not pitch creative on the basis of gut feeling. We build hypotheses, design experiments, measure outcomes, and scale what the data validates. In a marketing landscape full of opinion, we offer something rarer: evidence.

Founded in New York, we serve clients across North America and Europe — from growth-stage startups to established enterprises — across every channel where a direct-response mindset creates competitive advantage.

"The most important part of every advertisement is the headline. The headline is the telegram which decides whether people will read your copy." — John Caples, Tested Advertising Methods, 1932.

Caples' split-testing methods are the direct ancestor of every modern A/B test, multivariate experiment, and conversion rate optimisation programme run by digital marketers today.

Our Principles

How we think,
how we work.

Test Everything

No assumption is too small to test. From subject lines to landing page headlines, from bidding strategies to audience segments — if it touches performance, we run a structured experiment on it. Caples tested newspaper headlines with coded coupons. We test digital variants with statistical significance thresholds. The principle is identical.

Measure What Matters

Vanity metrics are comfortable. Revenue metrics are useful. We build measurement frameworks that connect marketing activity to business outcomes — pipeline, revenue, retention, lifetime value. Our clients always know which number moved and why. We refuse to hide behind impressions and reach when we can show return on investment.

Write to the Reader

Caples' greatest lesson was not about testing — it was about empathy. His headlines worked because they understood what the reader feared, wanted, and hoped for. Every word of copy we write, every ad we produce, every email we send is written for one specific person in one specific moment. Relevance is the multiplier on every other metric.

Never Guess When You Can Know

This was Caples' operating philosophy, and it is ours. When a client asks us which channel to invest in, we build a test. When they ask whether a message is resonating, we measure response rates. When they ask if a campaign is working, we show them attribution data. In every situation where a decision can be informed by data, we insist on informing it.

The Team

Strategists, analysts,
and storytellers.

Marcus Holt

Founder & CEO

Fifteen years in direct-response advertising across New York and London. Marcus built his first split-testing framework at 22 and has never stopped iterating. He leads strategy for our largest accounts.

Olivia Chen

Head of Performance

Former head of paid media at a Fortune 500 retailer. Olivia manages over $40M in annual media spend and holds the agency record for single-campaign ROAS: 14.2x on a Google Shopping rebuild.

Rafael Vargas

Head of Analytics & CRO

Statistician turned marketer. Rafael builds the attribution models, designs the experiments, and translates data into decisions. He has run over 2,000 A/B tests across client sites in six years at Caples Digital.

Eleanor Walsh

Head of Content Strategy

Award-winning editorial director with roots in long-form journalism. Eleanor leads our content practice, ensuring every piece earns its place in a reader's attention and a search engine's results.

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Work With Us

Ready to market with certainty instead of hope?

Book a free 30-minute strategy call. We'll identify your biggest growth opportunity and tell you exactly how we'd approach it.

No pitch deck. No pressure. Just an honest conversation.