GPT-5.5 vs Gemini 3.6 Flash
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
| Specification |
by OpenAI
|
Gemini 3.6 FlashIntro price
by Google
|
|---|---|---|
| Overview | ||
| Status | Current flagship | Current flagship |
| Released | ||
| Pricing per million tokens | ||
| Input | $5.00/Mtok | $0.750/Mtok |
| Output | $30.00/Mtok | $3.75/Mtok |
| Blended avg | $11.25/Mtok | $1.50/Mtok |
| Cached input | $0.500/Mtok | $0.075/Mtok |
| Price basis | — | Google's Gemini API pricing page prints a dated, two-phase schedule for this model: $0.75 per 1M input tokens through December 31, 2026, rising to $1.50 on January 1, 2027, and $3.75 per 1M output tokens through December 31, 2026, rising to $7.50. Context caching follows the same dates ($0.075, then $0.15). We publish the rate you would pay today and re-verify it before the changeover date. Checked 2026-08-13 against ai.google.dev/gemini-api/docs/pricing; the same page listed a flat $1.50/$7.50 on 2026-08-09, so this is a genuine 50% price cut rather than a correction to an earlier mistake. |
| Specifications | ||
| Context window | 1M tokens | 1M tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimageaudio
|
textimageaudiovideo
|
| Benchmarks sources: Vellum LLM Leaderboard / Artificial Analysis, Google DeepMind Gemini 3.6 Flash model card, LMSYS Chatbot Arena (UC Berkeley) | ||
| Terminal-Bench 2.1 | 82.7 | 78 vendor |
| OSWorld-Verified | 78.7 | 83 vendor |
| Avg benchmark score | 75 | — |
| Perf / dollar | 6.7 | — |
| GPQA Diamond | 93.6 | — |
| MCP Atlas | 75.3 | — |
| BrowseComp | 84.4 | — |
| Humanity's Last Exam | 41.4 | — |
| ARC-AGI 2 | 85 | — |
| HumanEval | 58.6 | — |
| AutoBench | 12.9 | — |
| Independent composite scores each on its own scale — not part of the average above | ||
| AA Intelligence Index | 56.3 | 51.6 |
| AA Agentic Index | 47.4 | 40.5 |
| AA-Omniscience Index (−100–100) | 20.5 | 22.1 |
| GDPval-AA v2 | 1491.1 ELO | 1422.3 ELO |
| LMSYS Chatbot Arena | 1477.2 ELO | 1480.2 ELO |
| Providers | ||
| Available from |
OpenAI — $5.00/$30.00/Mtok
|
Google — $0.750/$3.75/Mtok
|
Cost at scale
1M tokens · 50/50 input/output| Volume | GPT-5.5 | Gemini 3.6 Flash | Savings |
|---|---|---|---|
| 1M tokens | $11.25 | $1.5 | $9.75 (86.7%) |
| 10M tokens | $112.5 | $15 | $97.5 (86.7%) |
| 100M tokens | $1125 | $150 | $975 (86.7%) |
| 1000M tokens | $11250 | $1500 | $9750 (86.7%) |
When to pick which
distilled from the pricing and spec data above- this pairing gives GPT-5.5 no edge on price, context, cache discount, or measured performance — pick it only for qualitative fit (ecosystem, compliance, model behavior on your prompts)
- cost dominates: $1.50/Mtok blended vs $11.25 — 86.7% less on the same 50/50 token mix
Price movement
recorded changes since we began tracking each model · last checked| Model | Changes | Latest move | Old → new $/M |
|---|---|---|---|
| GPT-5.5 | 0 | — no move | Stable since we began tracking — no change recorded |
| Gemini 3.6 Flash | 1 | price cut on | $1.5/$7.5 → $0.75/$3.75/Mtok |
The cheaper option here — Gemini 3.6 Flash costs $1.50/Mtok blended on Google.
Summary
GPT-5.5 by OpenAI costs $5.00/Mtok input and $30.00/Mtok output, with a 1M-token context window. It supports text, image, audio input.
Gemini 3.6 Flash by Google costs $0.750/Mtok input and $3.75/Mtok output, with a 1M-token context window. It supports text, image, audio, video input.
On a blended cost basis, Gemini 3.6 Flash is 86.7% cheaper than GPT-5.5.
The two aren't directly comparable on average benchmark score: GPT-5.5 has published per-benchmark results, while Gemini 3.6 Flash does not yet — it is measured today on independent composites (see the table above).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.