case study

The Floor Is 3%. The Ceiling Is Yours.

Kut from the Kloth, a premium denim and apparel brand, is one of the best-performing brands in Nostra's portfolio. A full year into the partnership, Nostra ran a live holdout test on their production traffic, and shoppers who served the Nostra-accelerated experience were converting 17.01% higher than the control group.
CVR Lift
+17.01% CVR Lift
Minimum CVR Improvement
+3%
Minimum CVR Improvement
+3%
"The thing that sold me on Nostra is simple: they don't get paid unless they actually generate revenue for us. Most vendors promise results. Nostra puts their own paycheck on the line to prove it — and a year in, they were still driving a 17% lift on a live holdout. That's a partner, not a vendor."
Steve M.
Head of Growth
01

Why Kut from the Kloth hit 17%+ CVR

No single variable explains a 17.01% lift. But there's a clear profile that separates the brands at the top of our distribution from the brands in the middle. If you share it, that ceiling is in reach for you too.

Catalog and category dynamics. Apparel, and premium denim specifically, is unusually sensitive to trust cues. Shoppers are spending real money on items they can't try on. Speed reads as confidence, polish, and legitimacy. A fraction of a second on a product page can meaningfully shift whether someone adds to cart.

Mobile share and traffic mix. Brands with more mobile traffic, more paid acquisition, and more first-time visitors typically see the biggest lifts, because those audiences are the most latency-sensitive and the most likely to bounce on a slow experience.

How slow they were before. The bigger the gap between a brand's pre-Nostra experience and what the web is capable of, the bigger the room for lift. Brands with heavier theme stacks, more third-party apps, or mobile-heavy audiences on flaky networks tend to see outsized gains.

Kut from the Kloth checks all three boxes. They're not a freak result. They're what the math looks like when the conditions line up. Plenty of brands fit this profile, and when they do, double-digit lifts stop being surprising.

02

What You Should Actually Expect

If you're evaluating Nostra, here's the honest frame.

Nostra doesn't make money unless you do too. Our pricing is performance-based. If we don't drive a lift on your live holdout, we don't get paid. That's why we're comfortable putting numbers in writing instead of hedging.

We commit to a minimum 3% conversion rate lift. That's the floor, not the goal, not the projection. The floor. If we don't clear it, we haven't done our job. At most brands' scale, even that floor is already a meaningful revenue event, worth the spend many times over.

But the floor isn't the ceiling. The brands that share Kut from the Kloth's profile (slow today, trust-sensitive category, heavy mobile and paid mix) consistently land well above it. A real share land where Kut from the Kloth did.

We don't pre-assign you a number. We measure it with a live production A/B test, not an attribution model. You'll see exactly what Nostra is worth on your own traffic, under your own conditions. The 3% is our promise. The 17% is what's possible when the profile lines up. If yours looks like Kut from the Kloth's, there's a real path to a result that looks like theirs.

03

How We Know These Numbers Are Real

The 17.01% at Kut from the Kloth wasn't a launch-day reading, a modeled estimate, or a number pulled from a synthetic benchmark. It came from a live holdout group on production traffic. A statistically significant segment of shoppers was served the unaccelerated experience and measured against the rest, twelve months into the partnership.

That's the same way we'll measure your number. A live A/B test on your real traffic, with a real holdout, run continuously. No attribution models, no estimated assists, no marketing math. Just a side-by-side comparison of shoppers who got Nostra and shoppers who didn't.

It's also why our 3% baseline isn't a marketing claim. We can put a number in writing because the same test that proves it is the same test that decides whether we get paid. Most performance vendors won't put their pay on the line. We do.

THE IMPACT

17.01% CVR Lift

Measured via live holdout on production traffic, twelve months into the partnership. Not a launch-day spike, a sustained, compounding result.

3% Guaranteed Floor

Nostra commits to a minimum 3% CVR lift. Performance-based pricing means if they don't clear it, they don't get paid. The floor isn't a goal — it's a promise.

It's a Profile, Not a Lottery

Trust-sensitive category, heavy mobile traffic, paid acquisition, first-time visitors, heavier tech stacks — brands that fit this profile consistently land well above the median.

Measured, Not Modeled

Every number comes from a live production A/B test — a statistically significant holdout group served the unaccelerated experience, measured against the rest. No attribution models, no synthetic benchmarks.

Turn Visitors Into Customers

300+ enterprise and high-growth brands rely on Nostra to deliver instant site speed, stronger SEO performance, deeper personalization, and clean, actionable marketing data.

Trusted by 300+ brands

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