Internet status in Japan Operational
Address blocks silent right now: 0% · 2026-10-21 00:08:24 UTC
Leading providers
| Provider | ASN | Share of users | Status | Signal dip |
|---|---|---|---|---|
| KDDI | AS2516 | 19.5% | Operational | 0% |
| SoftBank | AS17676 | 18% | Operational | 0% |
| NTT Docomo Business | AS4713 | 11.2% | Operational | 0% |
| NTT Docomo | AS9605 | 6.2% | Operational | 1% |
| Optage | AS17511 | 4.7% | Operational | 0% |
| JCOM Co. | AS9824 | 4.5% | Operational | 2% |
| Biglobe | AS2518 | 4.1% | Operational | 1% |
| Sony Network | AS2527 | 3.8% | Operational | 0% |
ℹ️ How to read this page
Degraded - signal dip ≥20% below its 24h baseline - partial outage or major disturbance
Major outage - dip ≥50% - large-scale loss of connectivity
“Signal dip” compares the current BGP-visibility and active-probing levels against the median of the previous 24 hours, corrected for global measurement artifacts (a worldwide simultaneous drop is ignored).
Data refreshes hourly. Per-ISP rows are measured in depth when the country shows an anomaly (pilot countries - continuously). The probable cause is a heuristic: an active fault on a submarine cable feeding the country ranks first, then routing signals, then power/access patterns.
Recorded outages in Japan
No country-level outages recorded for Japan since 21 Jun 2026.
Submarine cables feeding Japan
If a national outage coincides with a fault on one of these systems, the cable is a likely cause - check its live page:
Incident history
Significant incidents on cables landing here, each with its own report.
- Asia Submarine-cable Express (ASE)/Cahaya Malaysia: latency up to 3× normal, 9 Sep 2026 (resolved)
- Asia Pacific Gateway (APG) cable: latency up to 2.3× normal, 17 Apr 2026 (resolved)
- Asia Pacific Gateway (APG) cable: latency up to 2.5× normal, 17 Apr 2026 (resolved)
- Apricot cable: latency up to 2.4× normal, 15 Mar 2026 (resolved)
Internet in Japan: questions and answers
Is the internet down in Japan right now?
No. At the last check (21 Oct 2026 00:08 UTC) the internet in Japan was working normally: the signal was at its usual level.
When was the last internet outage in Japan?
No country-level outages have been recorded for Japan since 21 Jun 2026, when the records begin.
Which internet providers are watched in Japan?
GeoCables watches the leading providers of Japan: KDDI (19.5%), SoftBank (18%), NTT Docomo Business (11.2%), NTT Docomo (6.2%), Optage (4.7%). The share is the part of the country's internet users served by the provider.
Which submarine cables connect Japan?
Japan is connected by 53 submarine cables in the GeoCables database, among them 5 Villages 6 Islands, APCN-2, Apricot, Asia Direct Cable (ADC). A break on one of them can slow down or cut international traffic.
How does GeoCables detect an internet outage?
The status comes from two independent signals: routing announcements (BGP) and active probing of networks inside the country. A drop of 20% or more below the usual level of the last 24 hours is shown as degraded, a drop of 50% or more as an outage. See internet outages in all countries.