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Performance Score

pro
GET/v1/score/performance

Calculates a composite website performance score (0-100) from 6 weighted components: content compression (20%), HTTP protocol version (20%), cache policy effectiveness (20%), response time / TTFB (20%), resource hints (10%), and CDN detection (10%). Returns a letter grade (A+ to F), individual metric scores, and prioritized optimization opportunities with estimated impact. Scoring covers server-side performance factors complementing client-side metrics like Google Lighthouse and Core Web Vitals.

What It Does

Analyzes 6 server-side performance factors in parallel. Compression scoring (max 20 pts) evaluates Content-Encoding — Brotli earns 20 pts, Gzip earns 18 pts, Deflate earns 15 pts, no compression earns 0 pts. HTTP version scoring (max 20 pts) awards 20 pts for HTTP/3 (RFC 9114, QUIC-based), 15 pts for HTTP/2 (RFC 9113), and 5 pts for HTTP/1.1. Cache policy scoring (max 20 pts) analyzes Cache-Control headers — 20 pts for TTL over 1 day, 18 pts for 1+ hour, 15 pts for 5+ minutes, 12 pts for shorter TTLs, per RFC 9111 HTTP Caching semantics. Response time scoring (max 20 pts) measures TTFB — 20 pts for under 200ms, 15 pts for under 500ms, 10 pts for under 1 second, 5 pts for under 2 seconds. Resource hints scoring (max 10 pts) checks for preconnect (4 pts), preload (4 pts), and dns-prefetch (2 pts) headers. CDN detection scoring (10 pts) identifies CDN provider signatures (Cloudflare, Fastly, Akamai, etc.).

Why It's Useful

Website performance directly impacts user experience, conversion rates, and search rankings. Google uses Core Web Vitals as a ranking signal, and HTTP Archive data shows only 48% of mobile sites pass all three CWV thresholds. A single server-side performance score enables rapid benchmarking against competitors, tracking optimization progress over time, and identifying which infrastructure changes have the highest impact. The component breakdown shows exactly where optimization effort should be focused — upgrading to HTTP/3 and enabling Brotli compression are often the highest-impact changes.

Use Cases

Product Manager / SEO Manager

Competitive Performance Benchmarking

Score your domain and competitor domains to establish performance benchmarks. Track scores monthly to measure the impact of infrastructure investments. Compare HTTP version adoption, compression, and CDN usage across your competitive landscape.

Data-driven performance targets based on competitive analysis rather than arbitrary thresholds.

Performance Engineer / SRE

Infrastructure Optimization Prioritization

Use the component breakdown to identify the highest-impact optimization opportunities. A domain scoring 5/20 on HTTP version (HTTP/1.1) with 0/20 on compression has clear, actionable priorities. Track score improvements after each infrastructure change.

Focus optimization effort on the changes that will move the score most — avoid wasting time on marginal improvements.

Web Developer / DevOps Engineer

Pre-Launch Performance Validation

Run performance score checks as part of CI/CD pipelines before deploying to production. Set minimum score thresholds (e.g., grade B or above) as deployment gates. Catch misconfigurations like missing compression headers or cache policies before users are affected.

Prevent performance regressions from reaching production — catch missing Cache-Control headers, disabled compression, and protocol downgrades automatically.

Infrastructure Architect

Vendor & CDN Performance Assessment

Compare performance scores before and after CDN migrations, hosting changes, or origin server upgrades. Evaluate whether a CDN provider actually improves TTFB, compression, and cache hit rates for your specific traffic patterns.

Quantified infrastructure investment ROI — measure the actual performance impact of hosting and CDN decisions.

Parameters

NameTypeRequiredDescription
domainstringRequiredThe domain to calculate performance score for. TTFB is measured via HTTPS request.Example: google.com
samplesnumberOptionalNumber of measurement samples for response time averaging (1-5, default: 3).Example: 3

Response Fields

FieldTypeDescription
domainstringThe scored domain
scorenumberComposite performance score 0-100 (weighted sum of 6 components)
gradestringLetter grade: A+ (95-100), A (85-94), B (70-84), C (50-69), D (30-49), F (0-29)
gradeDescriptionstringHuman-readable description of the grade level
breakdownobjectIndividual component scores with score, max, and details for each of the 6 factors
breakdown.compressionobjectContent-Encoding analysis: Brotli, Gzip, Deflate, or none (max 20 pts)
breakdown.httpVersionobjectHTTP protocol version: HTTP/3, HTTP/2, or HTTP/1.1 (max 20 pts)
breakdown.cacheobjectCache-Control header analysis and TTL evaluation (max 20 pts)
breakdown.responseTimeobjectTTFB measurement in milliseconds (max 20 pts)
breakdown.resourceHintsobjectpreconnect, preload, dns-prefetch header detection (max 10 pts)
breakdown.cdnobjectCDN provider detection and identification (max 10 pts)
recommendationsarrayOptimization recommendations ranked by estimated score impact
componentCountnumberNumber of scoring components evaluated

Code Examples

cURL
curl "https://api.edgedns.dev/v1/score/performance" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d "domain=google.com"
JavaScript
const response = await fetch(
  'https://api.edgedns.dev/v1/score/performance?domain=google.com',
  {
    headers: {
      'Authorization': 'Bearer YOUR_API_KEY'
    }
  }
);

const data = await response.json();
console.log(data);
Python
import requests

response = requests.get(
    'https://api.edgedns.dev/v1/score/performance',
    headers={'Authorization': 'Bearer YOUR_API_KEY'},
    params={
    'domain': 'google.com'
    }
)

data = response.json()
print(data)

Read the full Performance Score guide

Why it matters, real-world use cases, parameters, response fields, and how to call it from Claude, ChatGPT, or Gemini via MCP.

Read the guide →

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External References

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