The Crypto Altseason Index crossed 75 on April 5, 2026 — the threshold historically used to define a confirmed altseason, meaning more than 75% of the top 100 altcoins have outperformed BTC over 90 days. SOL surged 41% on the week to reach $298, within striking distance of its all-time high at $307. SUI exploded 67% after a major DEX volume record and L2 bridge integrations.
AVAX, INJ, and TIA each gained 25–35%. Total altcoin market cap hit $1.28T — up from $820B three weeks ago. BTC dominance dropped from 61.2% to 54.8%, the sharpest weekly dominance decline since June 2024.
Derivatives data shows alt OI-to-BTC-OI ratio at 1.82 — in the range seen during the 2021 peak alt rally. The playbook from here: SOL, SUI, and L2 tokens are first movers; mid-caps typically follow 2–3 weeks later.