Anthropic API Gross Margin Estimated Above 80% as Inference Margin Reaches Mid-60s

Anthropic’s blended inference gross margin was estimated at the mid-60% range, while its application programming interface business was estimated to exceed an 80% gross margin, highlighting the different economics of usage-based services and consumer subscriptions.

Inference gross margin measures revenue remaining after the direct cost of running a trained model for users. It excludes research, training, sales, administration, financing costs and future infrastructure commitments.

Usage-based API services were estimated to account for 75% to 85% of Anthropic’s annual recurring revenue. Subscriptions represent about 10% of revenue but consume more than 40% of inference computing capacity. The subscription mix was estimated to lower blended revenue per megawatt by approximately $36 million.

Anthropic’s blended inference gross margin was estimated at 38% in 2025 and negative 94% in 2024 before reaching the mid-60% range. The API business was estimated to have a gross margin above 80%.

Subscription profitability varies with customer usage. Using a 92% API gross-margin assumption, modeled subscription margins at 100% utilization were negative 369% for Opus 5.5 and 1% for Fable 5.1. At 20% utilization, the modeled margins rose to 6% and 80%, respectively.

The estimates show higher modeled margins for API services than for subscriptions because API customers pay for actual usage, while consumer plans provide a fixed level of access. Higher usage can therefore increase the cost of serving a subscription without a matching increase in revenue.

The modeled results indicate that subscription plans could produce software-like margins if customers primarily used Fable. The figures are analytical estimates of Anthropic’s unit economics rather than company-confirmed financial disclosures.