How Many Tokens Am I Spending?

The Question

• How many tokens I'm spending?

Setup

• curl, claude-sonnet-5, claude-opus-5-5

Results

• How many tokens are used?

claude-sonnet-5

curl https://api.anthropic.com/v1/messages/count_tokens \
  -H "x-api-key: $ANTHROPIC_API_KEY" \
  -H "content-type: application/json" \
  -H "anthropic-version: 2023-06-01" \
  -d '{
    "model": "claude-sonnet-5",
    "messages": [{
      "role": "user",
      "content": "how many tokens is this sentence?"
    }]
  }'
{"input_tokens":17} <--------

claude-opus-5-5

curl https://api.anthropic.com/v1/messages/count_tokens \
  -H "x-api-key: $ANTHROPIC_API_KEY" \
  -H "content-type: application/json" \
  -H "anthropic-version: 2023-06-01" \
  -d '{
    "model": "claude-opus-5-5",
    "messages": [{
      "role": "user",
      "content": "how many tokens is this sentence?"
    }]
  }'
{"input_tokens":19} <--------

What I learned

• Not all LLMs "charge" the same amount of tokens
• Available tokens are directly correlated with the chosen LLM and context

GIT Repository

• N/A

Log

• 2026-09-25 — Starting with something simple.