Calyx Global, in collaboration with ClearBlue Markets, has developed a set of pioneering indices that offer carbon market stakeholders a trusted benchmark for assessing carbon market integrity and its associated pricing. These indices—the Calyx Global Carbon Integrity Index™ and the Calyx-ClearBlue Carbon Price-Integrity Index™—are designed as key tools to enhance transparency and build confidence in carbon credits issued and retired within the voluntary carbon market (VCM). By fostering a deeper understanding of market fundamentals, these indices aim to incentivize the development and utilization of high-integrity credits that drive credible climate impact.
These indices serve as critical barometers of the market’s overall integrity and resilience. The VCM has encountered headwinds in recent years and can only achieve sustained growth and stability if market confidence is restored. Such confidence hinges on verifiable claims of greenhouse gas (GHG) reductions or removals. Ideally, the price of credits should reflect their underlying quality—with premium prices awarded to high-quality credits. This pricing dynamic would not only stimulate the production of superior credits but also support broader climate objectives. Encouragingly, a recent increase in the correlation between GHG integrity and pricing indicates positive momentum for this emerging and gradually maturing market.
This analysis is made possible through the integration of two robust datasets focused on carbon credit quality and pricing. The indices leverage data from more than 890 distinct projects rated by Calyx Global, along with over 200,000 pricing data points provided by ClearBlue Markets.
The indices are updated monthly to reflect the latest average price by rating tier, as well as month-to-date and year-to-date index values. Stakeholders can track the indices and access the jointly published report, The State of Quality and Pricing in the VCM – February 2025, via our website.
Calyx-ClearBlue Carbon Price-Integrity Index
The Calyx-ClearBlue Carbon Price-Integrity Index has expanded its scope, now encompassing 352 projects—an increase of 28% from the 274 projects included in the inaugural February 2025 report. This growth reflects the incorporation of newly rated projects by Calyx Global and an expanded dataset of price observations from ClearBlue Markets.
The premium commanded by Tier 1 (T1) credits continues to underscore the market’s evolving preference for quality. In April, T1 credits were priced, on average, 36% higher than Tier 3 (T3) credits, reinforcing the growing valuation gap tied to credit integrity. This premium was further supported by rising prices in select project types, notably Landfill Gas and Ozone Depleting Substances (ODS).
Momentum remains with T1 credits, as demand concentrates around high-integrity assets. April saw a 6.3% increase in average prices for T1 credits, while both Tier 2 (T2) and T3 credits recorded declines—signaling a sharpening distinction in how the market values quality.
Calyx Carbon Integrity Index
The Issuance Quality Index reached a record high of 5.1 in April, driven by strong volumes of high-quality credits from the waste sector, particularly landfill gas and wastewater projects. However, the upward trend was partially offset by the issuance of lower-integrity renewable energy credits, highlighting the mixed nature of new supply.
On the retirement side, quality showed modest improvement but remains constrained by the continued use of lower-tier credits. Among the ten projects that retired over one million credits in April, five were based on methodologies currently deemed ineligible by the Integrity Council for the Voluntary Carbon Market (ICVCM).
For more information, visit our dedicated webpage, or contact us about our VCM Market Intelligence services.