Bybit & Block Scholes: ETH-BTC volatility hits five-year high as ETH plays catch-up

DUBAI, UAE, June 17, 2025 /PRNewswire/ -- Bybit, the world's second-largest cryptocurrency exchange by trading volume, released a new options volatility report in collaboration with Block Scholes. The report shows a historic volatility divergence between Ethereum (ETH) and Bitcoin (BTC) during May 2025.

Key Highlights:

• In May 2025, ETH options exhibited historically high volatility premiums over BTC, driven by ETH's elevated realized volatility during a major price rally.
• The ETH-to-BTC implied volatility ratio for short-dated options surged past 2x — reaching a nearly five-year high.
• BTC's realized volatility fell below a long-standing 35% floor, breaking a 19-month trend.
• ETH's volatility term structure showed persistent inversion, with shorter-dated options pricing higher volatility than longer-dated ones.
• The implied volatility divergence coincided with ETH's outperformance, which included a 23% intraday rally amid key market events.

ETH-to-BTC Implied Volatility Expands to Five-Year High

Figure 1. BTC (green) and ETH (pink) at-the-money options’ implied volatility at the 30-day tenor. Source: Block Scholes

In May 2025, a notable dislocation in implied volatility emerged between ETH and BTC options. Implied volatility reflects market expectations for future price movement over an option's lifespan. At the start of the month, the ETH-to-BTC implied volatility ratio for 7-day options hovered around 1.5 — indicating that ETH options were priced with 50% higher expected volatility than BTC options.

By May 16, the ratio climbed above 2x, reaching a peak not seen since 2020, as BTC's implied volatility declined to its lowest levels since October 2023. This drop in BTC volatility broke below the 35% floor that had held for over 19 months, while ETH's short-tenor implied volatility remained elevated, though slightly below its May 10 high. The volatility spread was particularly pronounced in the 30-day tenor, reaching its widest point since mid-2022.

Realized Volatility Trends Underscore the Divergence

The sharp divergence in implied volatility was reinforced by trends in realized volatility — a measure of actual historical price movement. In May, ETH's realized volatility significantly outpaced BTC's across various tenors, fueling expectations for continued dispersion between the two assets.

On May 15, the 7-day realized volatility ratio between ETH and BTC peaked, closely followed by the implied volatility ratio — suggesting market participants expected ETH's higher volatility to persist. This trend is not new: the ETH-BTC volatility ratio has been climbing steadily since July 2024, amid both bull runs and periods of market stress.

ETH's standout performance in May was catalyzed by several factors, including positive US-UK trade news. ETH surged more than 23% on May 8 alone and continued to outperform BTC, which gained approximately 10% during the same period. Despite this momentum, ETH remained over 50% below its January 2025 peak and its all-time high.

#Bybit / #TheCryptoArk / #BybitReport

About Bybit

Bybit is the world's second-largest cryptocurrency exchange by trading volume, serving a global community of over 70 million users. Founded in 2018, Bybit is redefining openness in the decentralized world by creating a simpler, open and equal ecosystem for everyone. With a strong focus on Web3, Bybit partners strategically with leading blockchain protocols to provide robust infrastructure and drive on-chain innovation. Renowned for its secure custody, diverse marketplaces, intuitive user experience, and advanced blockchain tools, Bybit bridges the gap between TradFi and DeFi, empowering builders, creators, and enthusiasts to unlock the full potential of Web3. Discover the future of decentralized finance at Bybit.com.

For more details about Bybit, please visit Bybit Press
For media inquiries, please contact: For updates, please follow: Bybit's Communities and Social Media

Discord + | Facebook | Instagram | LinkedIn | Reddit | Telegram | TikTok | X | Youtube+