The Definitive Guide toAI Data Centers
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one-way fiber latency from distance alone (~5 ms per 1,000 km); ~1.6 ms RT per 100 mi before any processing

~0.80 ms / 100 miobserved

Value kindobserved — Reported measurements, counts, and specifications keep the precision and scope stated by their source; an exact specification is not treated as a range.
As of2025
SourceM2 Optics fiber-latency analysis (4.9 µs/km, n≈1.47) · Rule of thumb: 4.9 microseconds per kilometer at refractive index 1.47; equivalent to approximately 0.79 ms per 100 miles one way
Reviewchecking…review by 2026-08-14 · standard cadence
Recorded changeslast 2026-07-02
Claim idone-way-fiber-latency-from-distance-alone-5-ms

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