Claude Sonnet 5 vs Grok 4.5
Two reasoning-forward flagships with very different temperaments.
What the numbers say
- Grok 4.5 is about 1.7x cheaper on output tokens (66.0 vs 110 credits per 1M).
- Claude Sonnet 5 takes noticeably more context: 1M vs 500K tokens.
- Grok 4.5 is the newer release (July 2026 vs June 2026).
Derived from the live registry Zeplik routes and bills against. Credits: 1 credit = $0.10, raw provider rate with a 1.10x margin.
Side by side
Claude Sonnet 5
Anthropic
Sonnet 5 is Anthropic's most capable Sonnet-class model, with frontier performance across coding, agents, and professional work. It supports adaptive thinking with selectable reasoning effort levels (low, medium, high, max,...
- Provider
- Anthropic
- Context window
- 1M tokens
- Input price
- 22.0 credits / 1M tokens ($2.00 raw)
- Output price
- 110 credits / 1M tokens ($10.00 raw)
- Vision (image input)
- Yes
- Tool calling
- Yes
- Extended reasoning
- No
Best for
- Hard problems where answer quality matters more than cost: strategy, analysis, difficult writing
- Very long documents and codebases: a 1M-token window fits entire books or repositories in one conversation
- Working with images: screenshots, charts, photos and scanned documents alongside text
- Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows
Grok 4.5
xAI
Grok 4.5 is SpaceXAI's smartest model with frontier performance on coding, knowledge work, and STEM.
- Provider
- xAI
- Context window
- 500K tokens
- Input price
- 22.0 credits / 1M tokens ($2.00 raw)
- Output price
- 66.0 credits / 1M tokens ($6.00 raw)
- Vision (image input)
- Yes
- Tool calling
- Yes
- Extended reasoning
- No
Best for
- Hard problems where answer quality matters more than cost: strategy, analysis, difficult writing
- Very long documents and codebases: a 500K-token window fits entire books or repositories in one conversation
- Working with images: screenshots, charts, photos and scanned documents alongside text
- Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows
Try both on Zeplik
The honest answer to most model debates is to run your own prompt on both. Zeplik puts Claude Sonnet 5 and Grok 4.5 in the same chat, so you can switch mid-conversation and compare answers on the work you actually do.