Informational

    HTTP 103 Early Hints

    The server sends preliminary headers to allow the browser to start preloading resources before the final response.

    Check a URL for HTTP 103

    Paste any URL to see whether it currently returns 103. Runs a live HTTP probe and follows redirects.

    What does HTTP 103 mean?

    HTTP 103 Early Hints allows the server to send HTTP headers before the final response. Browsers can start preloading linked resources (CSS, fonts, scripts) while the server is still preparing the full response. This can significantly improve page load performance.

    Common Causes

    • •Server supports early hints for performance optimisation
    • •CDN/proxy sends preload hints
    • •Server uses Link headers for critical resources

    How to Fix It

    1. 1.This is a performance feature — no fix needed
    2. 2.To implement, configure your server to send Link headers with rel=preload

    SEO Impact

    Positive indirect impact. Faster page loads improve Core Web Vitals, which Google uses as a ranking signal.

    Monitor HTTP 103 with LemWatch

    LemWatch tracks Core Web Vitals including LCP. Sites using 103 Early Hints often see improved LCP scores.

    Related Status Codes

    100

    Continue

    200

    OK

    102

    Processing

    101

    Switching Protocols

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