Anthropic: Claude Sonnet 4.5 vs OpenAI: GPT-5

OpenAI: GPT-5 is cheaper than Anthropic: Claude Sonnet 4.5 by about 43% on a blended (75% input / 25% output) basis. Anthropic: Claude Sonnet 4.5 charges $3.000000 / $15.000000 per 1M input/output tokens; OpenAI: GPT-5 charges $1.250000 / $10.000000.

FieldAnthropic: Claude Sonnet 4.5OpenAI: GPT-5
Input $/Mtok$3.000000$1.250000
Output $/Mtok$15.000000$10.000000
Cache read $/Mtok$0.300000$0.125000
Cache write $/Mtok$3.750000–
Input $/Mcharn/a0.352142
Output $/Mcharn/a2.817139
Context window1000000400000
Tokenizerclaudeo200k

Price history

Same workload, monthly cost

Illustrative monthly cost at 10M tokens/month, split per workload preset. Not a substitute for the calculator, which uses your own volume, cache and batch assumptions.

WorkloadAnthropic: Claude Sonnet 4.5OpenAI: GPT-5
Coding agent$36.00$16.88
RAG chat$48.00$25.63
Summarisation (batch)$42.00$21.25
Classification$32.40$14.25
Chat assistant$78.00$47.50
Content generation$126.00$82.50

Cite this page

Anthropic: Claude Sonnet 4.5 vs OpenAI: GPT-5: $3.000000/$15.000000 vs $1.250000/$10.000000 per 1M tokens, as of 2026-10-04 (Token Barometer, https://tokenbarometer.com/compare/anthropic_claude-sonnet-4-5-vs-openai_gpt-5).

Anthropic: Claude Sonnet 4.5 page | OpenAI: GPT-5 page | Open in calculator