Gemini 3.6 Flash vs GPT-5.5 — LLM API Cost Comparison
Compare Gemini 3.6 Flash (Google) vs GPT-5.5 (OpenAI) on cost per million tokens, context window, and monthly spend.
Prices verified 2026-08-03 · Pricing may change — use the calculator for current estimates
- Input
- $1.5/1M tokens
- Output
- $7.5/1M tokens
- Context
- 1M tokens
- Released
- 2026-07
Latest stable Gemini Flash; agentic and multimodal workloads; 1M context
- Input
- $5/1M tokens
- Output
- $30/1M tokens
- Context
- 272K tokens
- Released
- 2026-04
Latest OpenAI frontier model; 272K context standard tier
Monthly Cost by Usage Tier (70% input / 30% output ratio)
| Usage | Gemini 3.6 Flash | GPT-5.5 | Cheaper by |
|---|---|---|---|
| Light (1M tokens) | $3.30 | $12.50 | Gemini 3.6 Flash (74%) |
| Moderate (10M tokens) | $33.00 | $125 | Gemini 3.6 Flash (74%) |
| Heavy (100M tokens) | $330 | $1,250 | Gemini 3.6 Flash (74%) |
| Very Heavy (1B tokens) | $3,300 | $12,500 | Gemini 3.6 Flash (74%) |
Frequently Asked Questions
Which is cheaper — Gemini 3.6 Flash or GPT-5.5?
For input tokens, Gemini 3.6 Flash is cheaper at $1.5/1M tokens — 3.3× less than $5/1M. For output tokens, Gemini 3.6 Flash wins at $7.5/1M vs $30/1M. At heavy workloads (100M tokens/month), the cost difference can be significant.
What is the context window difference between Gemini 3.6 Flash and GPT-5.5?
Gemini 3.6 Flash supports 1,048,576 tokens per request; GPT-5.5 supports 272,000 tokens. Gemini 3.6 Flash wins on context length, making it better for long documents, large codebases, or extended conversations without chunking.
When should I choose Gemini 3.6 Flash over GPT-5.5?
Choose Gemini 3.6 Flash (Google) if you prefer Google's ecosystem, tooling, or reliability track record. Latest stable Gemini Flash; agentic and multimodal workloads; 1M context. Choose GPT-5.5 (OpenAI) if Latest OpenAI frontier model; 272K context standard tier. the price/performance fits your workload better. Use this calculator to find the break-even point for your exact token volume.
How much does 1 billion tokens cost on Gemini 3.6 Flash vs GPT-5.5?
At 700M input + 300M output tokens (1B total): Gemini 3.6 Flash costs $3300; GPT-5.5 costs $12500. The difference is $9200/billion tokens at this 70/30 input/output ratio.