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core-js vs Fastly

Based on 1637 and 383 real audits

Metriccore-jsFastlyWinner
Performance3645Fastly
Accessibility8891Fastly
Best Practices8489Fastly
SEO9192Fastly
Security6566Fastly
TTFB385ms149msFastly
Composite7374Fastly
Performance
core-js
36
Fastly
45
Accessibility
core-js
88
Fastly
91
Security
core-js
65
Fastly
66
SEO
core-js
91
Fastly
92
Composite
core-js
73
Fastly
74

Fastly outperforms core-js in 7 of 7 categories, with a stronger composite score (74 vs 73). core-js leads in no categories.

When to choose core-js

core-js doesn't clearly lead Fastly in any category on the sampled sites — pick it based on developer experience, ecosystem, or existing team skills rather than the audit scores.

When to choose Fastly

Choose Fastly when your primary concern is server response time and performance. Its audit data shows consistent strength in these areas across the sampled sites.

How this comparison was built

Scores are medians across 1637 audited core-js sites and 383 audited Fastly sites in the BeaverCheck database. Every audit runs the same 100+ checks — Lighthouse performance, security headers, accessibility, SEO, server response time — against a real URL. No vendor input, no sponsorship, no affiliate links. Read the full methodology →

FAQ

Which is faster, core-js or Fastly?
Based on real BeaverCheck audits, Fastly sites score higher on Lighthouse performance (45 vs 36 on average).
Which has better security, core-js or Fastly?
Fastly sites score higher on security analysis (66 vs 65 on average).
Which has better accessibility, core-js or Fastly?
Accessibility scores measured by Lighthouse WCAG 2.1 checks favor Fastly (91 vs 88). Both technologies can be made fully accessible with care — the difference reflects common patterns in the sampled sites, not inherent platform limits.
Which is better for SEO, core-js or Fastly?
Fastly sites score higher on Lighthouse SEO signals (92 vs 91 on average), which cover meta tags, crawlability, mobile friendliness, and structured data. Content strategy and backlinks still matter more than platform choice for ranking.
Which has faster server response (TTFB), core-js or Fastly?
Fastly sites show lower Time to First Byte (149 ms vs 385 ms on average). TTFB depends heavily on hosting and CDN setup rather than the technology itself, but the sampled sites suggest a meaningful difference in common deployment patterns.
Should I choose core-js or Fastly for my website?
Both platforms have trade-offs. Fastly scores higher on overall composite score while core-js may excel in metrics you care about most. Run a free BeaverCheck audit on a real site using each to compare the metrics relevant to your use case.

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