OPENAI VS GOOGLE

GPT-5.6 Terra vs Gemini 3.5 Flash

Gemini 3.5 Flash is about 1.3x cheaper than GPT-5.6 Terra on a blended 3:1 input:output rate — the same 10K-in/2K-out request costs $0.033 vs $0.044. Gemini 3.5 Flash has the larger context window (1,048,576 vs 1,047,576 tokens).

Pricing verified

API pricing per 1M tokens

ModelInput / 1M tokensOutput / 1M tokensBlended (3:1 mix)
GPT-5.6 Terra$2.00$12.00$4.50
Gemini 3.5 Flash$1.50$9.00$3.375

Rates from official OpenAI pricing and official Google pricing, checked 2026-08-11.

What a real workload costs

Example: one request with 10,000 input tokens and 2,000 output tokens, then that request at 100,000 runs per month.

ModelPer request (10K in / 2K out)Per month (100K requests)Monthly delta
GPT-5.6 Terra$0.044$4,400+$1,100
Gemini 3.5 Flash$0.033$3,300—

Model your own prompt sizes and volumes in the token cost analyzer, or check caching savings with the prompt caching calculator.

Specs side by side

SpecGPT-5.6 TerraGemini 3.5 Flash
ProviderOpenAIGoogle
Context window1,047,576 tokens1,048,576 tokens
Model classGeneral textGeneral text
Tokenizero200k_base (exact, public)Proprietary (counts estimated)

Count tokens for each model on its own page: GPT-5.6 Terra token counter and Gemini 3.5 Flash token counter. All OpenAI models are on the OpenAI Token Counter. All Google models are on the Gemini Token Counter.

FAQ

GPT-5.6 Terra vs Gemini 3.5 Flash FAQ

Which is cheaper, GPT-5.6 Terra or Gemini 3.5 Flash?

Gemini 3.5 Flash is cheaper. At rates checked 2026-08-11, GPT-5.6 Terra costs $2.00 input / $12.00 output per 1M tokens, while Gemini 3.5 Flash costs $1.50 input / $9.00 output — about a 1.3x difference on a typical 3:1 input-heavy workload.

How much does a real request cost on GPT-5.6 Terra vs Gemini 3.5 Flash?

A request with 10,000 input tokens and 2,000 output tokens costs about $0.044 on GPT-5.6 Terra and $0.033 on Gemini 3.5 Flash. At 100,000 such requests per month that is $4,400 vs $3,300 — a difference of $1,100 per month.

Which has the bigger context window, GPT-5.6 Terra or Gemini 3.5 Flash?

Gemini 3.5 Flash. It supports 1,048,576 tokens of context versus 1,047,576 tokens — roughly 786,000 English words in one request.

Do GPT-5.6 Terra and Gemini 3.5 Flash count tokens the same way?

Not exactly. GPT-5.6 Terra uses the published o200k_base tokenizer and Gemini 3.5 Flash uses a proprietary tokenizer (counts are estimates). The same prompt will tokenize differently, which shifts effective cost per word.