The #1 BigCommerce Speed Optimization Agency
Expert BigCommerce Speed Optimization Services
Stencil theme audits, app profiling, checkout performance tuning, and headless optimization — engineered for BigCommerce stores that need to pass Core Web Vitals and convert more customers.
The average BigCommerce store takes over 4 seconds to load on mobile — well above Google's 2.5-second LCP threshold for a ranking boost. Bloated Stencil themes, too many apps injecting scripts, unoptimized product images, and heavy checkout pages compound into failing Core Web Vitals scores, abandoned carts, and lower search rankings. Our BigCommerce speed optimization service addresses every layer — from Stencil front-matter configuration and Handlebars template efficiency to app script deferral, Akamai CDN tuning, and Interaction to Next Paint (INP) fixes.
Trusted by leading brands
ROI Calculator
How Much Revenue Is Your Slow Site Costing You?
Enter your URL — in 30 seconds, you'll see exactly how much revenue slow speed is costing you.
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10,000+ sites analyzed · No login required · See your losses in 30 seconds
conversion loss per 1-second delay
of visitors leave after 3 seconds
Think with Google
in annual revenue lost to slow sites
Akamai
of consumers say speed affects purchases
Unbounce
higher bounce rate at 5s vs 1s load
of shoppers won't return to slow sites
Akamai
faster = 1% more conversions
Deloitte
sites analyzed by our tool
PageSpeed Matters
to form a first impression online
Google Research
abandon sites that take 3s+ to load
Portent
conversion loss per 1-second delay
of visitors leave after 3 seconds
Think with Google
in annual revenue lost to slow sites
Akamai
of consumers say speed affects purchases
Unbounce
higher bounce rate at 5s vs 1s load
of shoppers won't return to slow sites
Akamai
faster = 1% more conversions
Deloitte
sites analyzed by our tool
PageSpeed Matters
to form a first impression online
Google Research
abandon sites that take 3s+ to load
Portent
Who This Is For
Is This Right for You?
Product Stores
Product-based stores need fast collection pages, image-heavy product pages, and instant filtering.
B2B & Wholesale
B2B stores with customer-specific pricing and complex catalogs need fast search and account pages.
Multi-Storefront
Multi-storefront setups need each storefront independently optimized for its target audience.
Headless Commerce
Headless BigCommerce builds need optimized API calls, efficient data fetching, and fast client-side rendering.
Common Problems
What's Slowing You Down?
Stencil Theme Bloat
BigCommerce's Stencil themes accumulate customizations over time. Unused Handlebars partials, excessive front-matter data fetching, and render-blocking CSS/JS compound into slow page loads.
Guide: BigCommerce Stencil OptimizationApp Script Overload
Every installed BigCommerce app adds JavaScript, CSS, and API calls to your store. Reviews, upsells, chat widgets, and analytics tools compound into 2–4 seconds of extra load time.
Guide: BigCommerce App Impact RankingSlow Product & Category Pages
Large product catalogs with high-res images, variant selectors, and faceted search create heavy pages. Unoptimized product images alone can account for 60%+ of page weight.
Guide: BigCommerce Product Page SpeedCheckout & Cart Abandonment
Payment gateway scripts, shipping calculators, and third-party checkout integrations make the most revenue-critical pages the slowest — driving up cart abandonment rates.
Guide: BigCommerce Checkout SpeedOur Solutions
How We Fix It
Stencil Theme Profiling
We audit every Handlebars template for rendering efficiency, front-matter data over-fetching, unused partials, and CSS/JS bloat. You receive a ranked impact report with specific optimization recommendations and before/after render times.
App Impact Analysis & Cleanup
We profile every installed app individually for JavaScript weight, API call overhead, and render-blocking behavior. You get a ranked report showing exactly which apps cost the most speed, with vetted faster alternatives and migration steps.
Image & Asset Optimization
We implement responsive srcsets, modern formats (WebP/AVIF), proper lazy loading, and Akamai CDN optimization for all product images, hero banners, and category thumbnails — without sacrificing visual quality.
Checkout Performance Engineering
We defer non-critical payment gateway scripts, optimize shipping rate calculations, reduce DOM complexity on checkout, and ensure the most revenue-critical pages load in under 2 seconds.
Core Web Vitals Engineering
We target LCP, INP, and CLS individually — fixing layout shifts from product galleries, optimizing interaction handlers on collection pages, and monitoring real-user CrUX data until all metrics pass Google's 28-day rolling window.
Performance Safeguarding
After deployment, we provide 30 days of monitoring to catch regressions from app updates, theme changes, or BigCommerce platform updates. You receive a Speed Budget Document with max JS size, image targets, and app limits.
The Data
Why Speed Matters for BigCommerce Stores
Every study points to the same conclusion — faster stores make more money.
Proof
Our Results
Real stores, real speed improvements, real revenue impact.
Liz Mathe
Stencil theme optimization with improved PageSpeed and Core Web Vitals across all product pages.
View Case Study
Platterful
80% speed improvement, 20% conversion lift. Mobile score from 50s to 90+.
View Case Study
Pure Parima
38% LCP improvement, 100% CLS fix. Passed all Core Web Vitals.
View Case StudyOur Process
How It Works
Staging & Full Audit
We run a comprehensive performance audit — PageSpeed, Core Web Vitals, Stencil template profiling, app script analysis, and real-device testing. Your live store is never touched during this phase.
App & Template Impact Ranking
Every installed app and Stencil template is profiled individually for rendering time, JavaScript footprint, and API overhead. You receive a ranked report showing exactly which components cost the most speed.
Optimization Sprint
1–2 WeeksOver 1–2 weeks, we implement all fixes: Stencil template optimization, app script deferral, Critical CSS generation, image optimization, and checkout tuning. Zero downtime to your live store.
Core Web Vitals Fine-Tuning
2–4 WeeksWe monitor real-user field data (CrUX) over 2–4 weeks, making iterative adjustments until LCP, INP, and CLS consistently pass in Google's 28-day rolling window — not just lab scores.
Deployment & Documentation
Once validated, all changes go live. You receive complete documentation of every change made, a speed budget for future development, and a before/after performance report.
Deliverables
What You'll Receive
Every engagement includes comprehensive documentation and reporting.
Before/After Speed Report
PageSpeed and Core Web Vitals scores before and after optimization, with waterfall comparisons.
App Impact Report
Every installed app ranked by JavaScript weight, API calls, and render-blocking behavior with specific load-time cost.
App Replacement Playbook
For every slow app identified, a vetted faster alternative with step-by-step migration instructions.
Stencil Theme Audit
Detailed analysis of Handlebars templates, front-matter configuration, and CSS/JS delivery with optimization results.
Competitor Speed Benchmark
How your store stacks up against 3–5 direct competitors on LCP, TTFB, and Speed Index.
Core Web Vitals Forecast
Projecting exactly which metrics (LCP, CLS, INP) will move into the 'Green' zone, with expected timelines.
Image Optimization Report
Analysis of product image delivery, format optimization, and CDN configuration with before/after file sizes.
Revenue Impact Projection
Custom report mapping your speed improvements to projected revenue gains using your actual traffic and conversion data.
Google Ads / CPC Savings Report
Analysis of how improved page speed lowers your Quality Score penalty and reduces cost-per-click for paid campaigns.
30-Day Post-Launch Monitoring
30 days of monitoring after deployment to ensure gains hold after app updates, theme changes, or platform updates.
SEO Impact Forecast
Projected ranking improvements based on Core Web Vitals fixes, with estimated organic traffic gains from your Search Console data.
Speed Budget Document
A living document setting performance budgets for future development — max JS size, image targets, app limits.
Executive Summary (1-Pager)
A non-technical summary for stakeholders showing what was done, what improved, and what it means in dollars.
Checkout Performance Audit
Page-by-page analysis of cart, checkout, and account pages with specific optimization recommendations.
Third-Party Script Analysis
Every external script identified and categorized with defer, async, or remove recommendations.
Pricing
Estimate Your Investment
Answer a few quick questions about your site to get an instant ballpark. Final pricing is confirmed after an audit.
How much traffic does your site get?
How much custom code does your site have?
How many third-party tools are running?
Do you need Core Web Vitals optimization?
How many posts/pages and products does your site have?
Estimated Investment
$1,500 – $2,500
One-time optimization fee
Typical Timeline
5–7 days
Why this range
simple setup
Final quote + plan confirmed after audit
What We Optimize
Apps, Themes & Pages
Storefront Optimization
Optimize BigCommerce's Stencil theme engine, Handlebars templates, and front-matter configuration for faster page rendering and reduced TTFB.
Script & Asset Management
Audit and optimize third-party scripts, defer non-critical JavaScript, implement critical CSS, and minimize render-blocking resources.
App & Integration Profiling
Profile every installed app and integration for performance impact. Identify bottlenecks from payment gateways, reviews, and marketing tools.
CDN & Caching
Optimize BigCommerce's built-in Akamai CDN configuration, implement advanced caching headers, and configure edge caching for global performance.
API & Headless Performance
Optimize GraphQL and REST API calls for headless BigCommerce builds. Reduce API latency and implement efficient data fetching patterns.
Product & Category Pages
Optimize product images, variant selectors, faceted search, and category page rendering for fast-loading pages that convert.
Deep Dives
BigCommerce Speed Guides
Go deeper with our free expert guides on BigCommerce performance.
FAQ
Frequently Asked Questions
Ready to Get Started?
Request an audit and see exactly how we can improve your BigCommerce store's performance.
