How Proof Nutrition Increased Conversions with FunnelKit Funnel Builder

Proof Nutrition had already built a loyal audience through fitness-focused content and science-backed supplement offerings.

As the brand expanded its range of functional nutrition products, it needed a checkout experience that could handle multiple product types while keeping the buying journey simple and trustworthy.

With FunnelKit Funnel Builder, Proof Nutrition created a smoother, more conversion-focused checkout experience inside WooCommerce.

The result was a cleaner buying journey, stronger customer confidence, and more opportunities to increase order value.

About Proof Nutrition

Proof Nutrition helps people improve their health, fitness, and performance through evidence-based supplements and functional nutrition products.

The brand was founded by Stan and Nikola, who have years of experience in fitness coaching and share a strong focus on science-backed health and nutrition principles.

Their platform is built around premium supplements designed to support better lifestyle choices, long-term health, and everyday performance.

Business Challenges of Proof Nutrition

As Proof Nutrition continued growing its online supplement business, the team wanted to create a faster, more modern buying experience from product page to checkout.

A few key features were missing from their ideal customer journey:

• The brand wanted a faster checkout process, without unnecessary extra steps in between, like the cart page
• They also wanted to offer cross-sell and upsell items in a modern way so users can easily add them to their cart.
• A replacement for the default WooCommerce checkout with a  cleaner, more mobile-friendly checkout with only the fields customers actually need.
• A no-code way to present last-minute add-on offers right before customers complete their purchase.

Proof Nutrition needed a solution that could bring all these conversion-focused features together into one seamless buying journey.

How FunnelKit Funnel Builder Solved Proof Nutrition’s Challenges

Proof Nutrition used FunnelKit Funnel Builder to connect a functional side cart, upsell, and checkout experience into a single, streamlined flow.

• Faster path to checkout

FunnelKit Slide Cart replaced the traditional multi-step flow with an instant side cart that opens on add-to-cart, letting customers move to checkout faster.

It also keeps the shopping journey uninterrupted.

• In-cart upsells

Frequently bought-together suggestions appear directly in the slide cart, allowing customers to add complementary products instantly.

This creates natural upsell opportunities at the exact moment of intent.

• Optimized checkout layout

The checkout was simplified by reducing unnecessary fields and restructuring the form for faster completion.

Email is placed at the top, shipping details are streamlined, and only essential inputs are kept.

• Better mobile checkout experience

Enhanced phone field with country flag selection and validation improves usability, especially for mobile shoppers.

The checkout feels lighter, faster, and easier to complete.

• One-click order bump on checkout

A final order bump is placed right before payment, allowing customers to add a relevant product with a single click.

This increases order value without disrupting the flow.

In Proof Nutrition’s Words

FunnelKit helped us bring everything together into one smooth buying experience. From the slide cart to checkout optimization and order bumps, it gave us the flexibility to design a journey that feels fast, clear, and aligned with how our customers actually shop. It’s made a noticeable difference in both simplicity and conversions.

Founders, Proof Nutrition

Results

A more conversion-focused checkout experience became especially valuable as Proof Nutrition expanded its range of functional nutrition products and supplements.

Key improvements included:

• A faster and more seamless path from product page to checkout
• Reduced friction during checkout, especially on mobile
• More natural upsell opportunities through slide cart and checkout offers
• A cleaner checkout structure that helps customers complete purchases with less hesitation
• Better support for selling multiple supplement types within one unified flow

Overall, the buying journey became simpler, more focused, and better aligned with how customers naturally purchase health and nutrition products online.

Proof Nutrition’s Future Plan With FunnelKit

Proof Nutrition continues to expand its range of functional nutrition products and supplement offerings.

With FunnelKit Funnel Builder, they’re able to keep refining the buying journey as they scale — bringing products, cart experience, and checkout optimization together into one streamlined flow that supports higher conversions and a smoother customer experience.