Gemini 2.5 Pro API Pricing question

Gemini API
,
1

Hello,sir.

Currently,i am thinking about paying Gemini 2.5 Pro API(upgrade to Tier 1 or 2 or 3)
I have few quetions

  1. would it be different for API price with Tier 1 or 2 or 3?
    2.I check Gemini API document for Gemini 2.5 Pro,and there are input price and output price.Does input price mean tokens i prompt?and output price means AI Responds?
  2. what is Context caching price ?
    Thanks
3
Tier Requests per Minute (RPM) Tokens per Minute (TPM) Requests per Day (RPD)
Tier 1 150 2,000,000 10,000
Tier 2 1,000 5,000,000 50,000
Tier 3 2,000 8,000,000 Unlimited

Here is the pricing doc link - Gemini Developer API Pricing  |  Gemini API  |  Google AI for Developers

Estimating Costs

To estimate your usage:

  • Input Tokens: Each token is approximately 4 bytes.
  • Output Tokens: Similar to input tokens in size.
  • Image Generation: Each image consumes about 1290 tokens.

For example, generating 1 million tokens of input and output text would cost approximately $0.50. Generating 1,000 images would cost about $39.00.