Problem Summary
You’re trying to compare Cloudflare and Fastly CDN performance for your website in 2025, but the benchmarks aren’t matching your real-world results or you’re seeing unexpected behavior. This matters because choosing the wrong CDN can cost you thousands in lost revenue from slow page loads and poor user experience.
Step-by-Step Fixes
Step 1: Clear Your Testing Environment
Start fresh by clearing all caches on both CDNs. Log into your Cloudflare dashboard and hit the “Purge Everything” button under Caching > Configuration. For Fastly, navigate to Configure > Purge > Purge All. Wait at least 5 minutes before running new tests.
This ensures you’re not comparing stale cached content from one CDN against fresh content from another.
Step 2: Use Multiple Testing Tools
Don’t rely on just one benchmark tool. Run tests using:
- GTmetrix from multiple locations
- WebPageTest with at least 3 runs per location
- Pingdom from different geographic regions
- Your browser’s built-in DevTools Network tab
Each tool measures slightly different metrics. GTmetrix focuses on overall performance scores while WebPageTest gives you detailed waterfall charts. Pingdom excels at uptime monitoring alongside speed tests.
Step 3: Match Your CDN Configurations
Open both CDN dashboards side by side. Check these critical settings:
- Compression levels (Brotli vs Gzip)
- Cache TTL values
- Security settings (WAF rules can slow performance)
- Image optimization features
- Minification settings for CSS/JS
Even small differences like Cloudflare using Brotli level 4 while Fastly uses level 6 can skew your benchmarks by 10-15%.
Step 4: Test During Peak Hours
Run benchmarks at different times:
- Morning (8-10 AM in your target timezone)
- Lunch hour (12-2 PM)
- Evening peak (6-9 PM)
- Late night (11 PM – 2 AM)
CDN performance varies dramatically based on network congestion. What looks fast at 3 AM might crawl during business hours.
Step 5: Check Your Origin Server
Your origin server might be the bottleneck, not the CDN. Use tools like:
“`bash
curl -w “@curl-format.txt” -o /dev/null -s https://yourdomain.com
“`
Create a curl-format.txt file with:
“`text
time_namelookup: %{time_namelookup}n
time_connect: %{time_connect}n
time_appconnect: %{time_appconnect}n
time_pretransfer: %{time_pretransfer}n
time_redirect: %{time_redirect}n
time_starttransfer: %{time_starttransfer}n
time_total: %{time_total}n
“`
If your origin response time exceeds 200ms, focus on optimizing your server before comparing CDNs.
Step 6: Verify DNS Resolution
Both Cloudflare and Fastly use anycast DNS, but resolution times can vary. Test with:
“`bash
dig yourdomain.com
nslookup yourdomain.com
“`
Look for resolution times under 50ms. Anything higher suggests DNS configuration issues that will affect all your benchmarks.
Likely Causes
Cause #1: Geographic Testing Bias
You might be testing from locations where one CDN has better infrastructure. Cloudflare has 300+ data centers globally while Fastly operates around 80 strategic POPs (Points of Presence). This means Cloudflare often wins in smaller cities while Fastly might excel in major metropolitan areas.
Check for this by running tests from at least 10 different global locations. Use VPNs or cloud testing services to simulate users from Asia, Europe, North America, and South America. If one CDN consistently wins in specific regions, you’ve found geographic bias.
Fix this by choosing the CDN that performs best where most of your users are located. Check your Google Analytics geographic data to make an informed decision.
Cause #2: Incorrect Cache Headers
Your cache headers might work perfectly with one CDN but cause issues with another. Cloudflare respects standard Cache-Control headers while Fastly requires more specific configuration through VCL (Varnish Configuration Language).
Check your headers using:
“`bash
curl -I https://yourdomain.com/sample-page
“`
Look for Cache-Control, Expires, and ETag headers. If they’re missing or set to “no-cache”, you’re not getting accurate CDN performance benchmarks.
Fix this by setting proper cache headers in your origin server. For Apache, add to .htaccess:
“`apache
ExpiresActive On
ExpiresByType image/jpg “access plus 1 year”
ExpiresByType image/jpeg “access plus 1 year”
ExpiresByType image/gif “access plus 1 year”
ExpiresByType image/png “access plus 1 year”
ExpiresByType text/css “access plus 1 month”
ExpiresByType application/javascript “access plus 1 month”
“`
Cause #3: Plan Limitations
Free or lower-tier plans often have performance restrictions. Cloudflare’s free plan includes basic CDN features but lacks advanced optimizations like Argo Smart Routing or Load Balancing. Fastly doesn’t offer a free tier, but their pay-as-you-go pricing might throttle performance during traffic spikes if you hit billing thresholds.
Check your current plan limits in both dashboards. Look for:
- Bandwidth restrictions
- Request limits per second
- Available features
- Geographic coverage limitations
Upgrade to comparable plans when benchmarking. Testing Cloudflare Pro against Fastly’s enterprise tier won’t give you meaningful comparisons.
When to Call a Technician
Consider hiring a CDN specialist or performance engineer when:
- Your benchmarks show wildly inconsistent results (variations over 50%)
- You’re losing more than $1,000 per month from slow load times
- You need custom VCL configuration for Fastly
- Your site serves over 10 million requests monthly
- You require multi-CDN setup for redundancy
A technician can set up proper A/B testing, implement RUM (Real User Monitoring), and create custom performance dashboards. They’ll also help negotiate enterprise contracts if you need advanced features from either provider.
Don’t struggle alone if your business depends on CDN performance. The cost of expert help is usually less than one month of lost revenue from a poorly configured CDN.
Copy-Paste Prompt for AI Help
“`
I’m comparing Cloudflare and Fastly CDN performance for my website in 2025. Here are my current results:
Website: [your domain]
Current CDN: [Cloudflare/Fastly/None]
Average load time: [X seconds]
Monthly traffic: [X visits]
Primary audience location: [country/region]
Current plan: [Free/Pro/Business/Enterprise]
Test results:
- GTmetrix score: [X]
- PageSpeed score: [X]
- Time to First Byte: [X ms]
My origin server: [hosting provider and plan]
Main content type: [static/dynamic/mixed]
Please help me:
- Identify why my benchmarks might be inaccurate
- Suggest specific settings to check in both CDNs
- Recommend which CDN fits my use case better
- Provide testing methodology for accurate comparison
“`
This comprehensive approach to benchmarking Cloudflare versus Fastly ensures you make the right choice for your specific needs in 2025. Remember that raw speed isn’t everything – consider reliability, ease of use, pricing, and support quality in your final decision.