Claude Opus 5.5 vs GPT-6 Astra: planning a higher-cost workload
When an expensive task is repeated at scale, output volume deserves its own budget. Opus 5.5 and GPT-6 Astra have different base text prices even though both document large context windows and output limits.
Budget the answer, including reasoning
Opus lists $4 input and $20 output per million tokens; Astra lists $10 and $50. These are standard direct API text rates, not a claim about how many tokens either model needs for your task. Include all billable reasoning output when estimating a long answer.
Capacity does not decide the task outcome
Opus documents a 1,000,000-token shared context window and Astra 1,050,000; both list a 128,000-token maximum output. A larger maximum does not demonstrate better handling of a particular document. Set your own retrieval or analysis checks before assigning a high-budget workload.
Avoid expanding the comparison beyond its evidence
The calculator excludes tools, media and provider processing-tier uplifts. If your workflow depends on those charges, a text-only estimate is incomplete. No benchmark rank, observed speed or quality premium is inferred from these prices.
Documented specifications and standard direct API rates, manually checked 2026-10-09. Evaluation suggestions are editorial guidance; no measured comparative quality or speed is claimed.
Unknown fields are not evidence of equal capabilities. Specifications describe support, not comparative answer quality.
BENCHMARK EVIDENCE
No reliable data available
Comparable results with confirmed reuse permission have not been published here yet.
A published result must include the exact model version, benchmark version, original value and unit, test date, conditions and source. No scores or overall rankings are inferred.
Text tokens only. Billable output includes reasoning tokens where applicable. Excludes cache creation, tools, media and regional or processing-tier uplifts.
Default 30-minute cache writes use 1.25× uncached input pricing as a replacement rate. V1 live trials request explicit-only caching with no breakpoints.
KNOW YOUR API COST
A small prompt. A clearer budget.
Same token counts for both models. Standard paid text rates in USD. Output must include all billable reasoning tokens.
Cached input is included in total input. No cache creation/storage, tools, media, taxes or regional/priority/Batch fees. Tokenizers differ; equal token counts do not imply equal text length.
49 estimated credits / comparison49,000 credits across 1,000 comparisons.Reference estimate only. Playground uses verified OpenRouter charges; 1,000 credits = $1. A + B round up together once for each comparison.
See how your prompt behaves.
Choose an enabled official model pair in the Playground. Your maximum reservation is shown before running; confirmed usage determines the final charge.