OpenAI: GPT-5.1-Codex-Max vs Anthropic Claude Opus 5.5: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing OpenAI: GPT-5.1-Codex-Max (openai/gpt-5.1-codex-max) vs Anthropic Claude Opus 5.5 (claude-opus-5-5). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
OpenAI: GPT-5.1-Codex-Max (openai/gpt-5.1-codex-max) Startup Credits & Batch API 50% Off Promo
OpenAI GPT-6.1 Sol ($2/$10 base rate) qualifies for immediate 75% automatic prefix caching ($0.50/1M), 50% off 24-hour Batch API completions ($1/$5), and up to $150,000 in OpenAI/Azure Foundry credits via Microsoft for Startups Founders Hub (no VC funding required for initial tiers).
Claude for Startups Program ($25,000 API Credits) & 95% Off Ephemeral Cache Reads
Anthropic's Q4 2026 developer promotion combines $25,000 in Claude API credits for early-stage builders with a permanent 20% base price reduction on Opus 5.5 ($4/$20), 0.05x ($0.20/1M) prompt cache reads, and 50% off Batch API processing ($2/$10 with 300K max output).
In Etuki October 2026 FinOps telemetry comparing OpenAI: GPT-5.1-Codex-Max (API ID: openai/gpt-5.1-codex-max) vs Anthropic Claude Opus 5.5 (API ID: claude-opus-5-5), OpenAI: GPT-5.1-Codex-Max offers lower standard input pricing at $1.25/1M tokens ($10/1M output), while Anthropic Claude Opus 5.5 leads in cached prefix economics at $0.2/1M tokens (95% discount). OpenAI: GPT-5.1-Codex-Max achieves a 70ms faster P90 time-to-first-token latency (280ms vs 350ms).
Auto-discovered via live global telemetry registry.
Adaptive thinking is always on; high effort generates ~119K thinking tokens/task. Fast mode costs $8/$40; inference_geo:"us" adds +10%.
| Specification / FinOps Dimension | OpenAI: GPT-5.1-Codex-Max | Anthropic Claude Opus 5.5 | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | openai/gpt-5.1-codex-max | claude-opus-5-5 | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $1.25 / $10 | $4 / $20 | OpenAI: GPT-5.1-Codex-Max |
| Cache Read Price (per 1M) | $0.625/1M (50% Off) | $0.2/1M (95% Off) | Anthropic Claude Opus 5.5 |
| Context Window / Max Output | 391K In / 125K Out | 1000K In / 128K Out | Anthropic Claude Opus 5.5 |
| P90 First-Token / Edge Latency | 280ms | 350ms | OpenAI: GPT-5.1-Codex-Max (-70ms) |
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasonin
Ranked #1 on Artificial Analysis Intelligence Index (Score 58). Cuts Opus 5 pricing by 20% and features 0.05x ($0.20/1M) cache reads.
Real-Time Stack Cost & Hidden-Fee Simulator (MAU / Token / Egress / GMV)
Calibrated with Reddit r/FinOps & r/devops telemetry: Includes Context Caching, Bandwidth Egress, and MoR Tax
🧠Switch from OpenAI: GPT-5.1-Codex-Max to Anthropic Claude Opus 5.5
Ranked #1 on Artificial Analysis Intelligence Index (Score 58). Cuts Opus 5 pricing by 20% and features 0.05x ($0.20/1M) cache reads. Verified P90 latency of 350ms.