Mistral AI Devstral Small vs OpenAI GPT-5.5: Live Promos, Pricing, Hidden Fees & Latency
Mistral AI Devstral Small (mistralai/devstral-small) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for Mistral AI Devstral Small: Activate ephemeral prefix caching to slash input costs by 90% (down to 0.01/1M) or route via asynchronous Batch API for 50% off standard token rates.
OpenAI GPT-5.5 (gpt-5.5-chat-latest) Startup Credits & Batch API 50% Off Promo
OpenAI GPT-6.1 Sol ($2/$10 base rate) qualifies for immediate 95% automatic prefix caching ($0.10/1M), 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).
In Etuki October 2026 FinOps telemetry comparing Mistral AI Devstral Small (API ID: mistralai/devstral-small) vs OpenAI GPT-5.5 (API ID: gpt-5.5-chat-latest), Mistral AI Devstral Small offers lower standard input pricing at $0.1/1M tokens ($0.3/1M output), while Mistral AI Devstral Small leads in cached prefix economics at $0.01/1M tokens (90% discount). Mistral AI Devstral Small achieves a 125ms faster P90 time-to-first-token latency (195ms vs 320ms).
Gateway-synced rate ($0.1/$0.3 per 1M, flat 128K window). Verify upstream provider cache TTL and regional routing before high-volume batch runs.
Official gpt-5.5-chat-latest cached input rate is $0.50/1M (90% off $5.00 input). Migrate to GPT-6.1 Sol ($2/$10, Cache $0.10) to cut spend by 50%.
| Specification / FinOps Dimension | Mistral AI Devstral Small | OpenAI GPT-5.5 | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | mistralai/devstral-small | gpt-5.5-chat-latest | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $0.1 / $0.3 | $5 / $30 | Mistral AI Devstral Small |
| Cache Read Price (per 1M) | $0.01/1M (90% Off) | $0.5/1M (90% Off) | Mistral AI Devstral Small |
| Context Window / Max Output | 128K In / 64K Out | 128K In / 128K Out | OpenAI GPT-5.5 |
| P90 First-Token / Edge Latency | 195ms | 320ms | Mistral AI Devstral Small (-125ms) |
Mistral AI Devstral Small (mistralai/devstral-small): OpenRouter gateway-synced model at $0.1/1M input, $0.3/1M output, $0.01/1M cached input (128K context window).
Flagship GPT-5 series general model with configurable reasoning_effort from none to xhigh.
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 Mistral AI Devstral Small to OpenAI GPT-5.5
Flagship GPT-5 series general model with configurable reasoning_effort from none to xhigh. Verified P90 latency of 320ms.