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IIS vs Microsoft IIS

Based on 80 and 72 real audits

View IIS details | View Microsoft IIS details
MetricIISMicrosoft IISWinner
Performance5045IIS
Accessibility8887IIS
Best Practices8685IIS
SEO9190IIS
Security6867IIS
TTFB519ms547msIIS
Composite7472IIS
Performance
IIS
50
Microsoft IIS
45
Accessibility
IIS
88
Microsoft IIS
87
Security
IIS
68
Microsoft IIS
67
SEO
IIS
91
Microsoft IIS
90
Composite
IIS
74
Microsoft IIS
72

IIS outperforms Microsoft IIS in 7 of 7 categories, with a stronger composite score (74 vs 72). Microsoft IIS leads in no categories.

When to choose IIS

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

When to choose Microsoft IIS

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

How this comparison was built

Scores are medians across 80 audited IIS sites and 72 audited Microsoft IIS 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, IIS or Microsoft IIS?
Based on real BeaverCheck audits, IIS sites score higher on Lighthouse performance (50 vs 45 on average).
Which has better security, IIS or Microsoft IIS?
IIS sites score higher on security analysis (68 vs 67 on average).
Which has better accessibility, IIS or Microsoft IIS?
Accessibility scores measured by Lighthouse WCAG 2.1 checks favor IIS (88 vs 87). 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, IIS or Microsoft IIS?
IIS sites score higher on Lighthouse SEO signals (91 vs 90 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), IIS or Microsoft IIS?
IIS sites show lower Time to First Byte (519 ms vs 547 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 IIS or Microsoft IIS for my website?
Both platforms have trade-offs. IIS scores higher on overall composite score while IIS 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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