Claude Sonnet 5
Chat model · Anthropic ·
Claude Sonnet 5 is a chat model by Anthropic. In Endless it costs 243 credits per 1M input tokens and 1215 per 1M output tokens, on every plan.
Claude Sonnet 5 is Anthropic's June 2026 Sonnet for coding, research and agent work, performing close to Claude Opus 4.8 on many tasks.
- Price
- 243 credits per 1M input tokens
- 1215 credits per 1M output tokens
- Availability
- Available on every plan
- Context window
- 1M tokens
- Max output
- 128K tokens
- Inputs
- Text, images
- Outputs
- Text
About Claude Sonnet 5
Claude Sonnet 5 launched in June 2026 as the most agentic Sonnet up to that point. It plans multi-step work, uses browsers and terminals and can keep going on its own. Compared with Claude Sonnet 4.6 it is a substantial improvement in reasoning, tool use, coding and knowledge work, and its results land close to Claude Opus 4.8. It reads text and images with a 1M-token context window.
It is at its best on existing codebases, where it ships a durable fix instead of patching the symptom. Use it for sustained coding and debugging, for business automations that run end to end, such as updating CRM records and then sending the related announcement, and for legal research and analysis.
Claude Sonnet 5.5 is now the current Sonnet, with faster output and stronger agentic coding. Sonnet 5 remains a steady choice when you want results consistent with work you already did on it, and both sit in the same Endless workspace.
Best for
- Debugging and fixing issues in existing codebases
- Multi-step automations that touch several tools
- Legal and business research with written analysis
Questions about Claude Sonnet 5
- What is Claude Sonnet 5?
- Claude Sonnet 5 is a chat model by Anthropic.
- Is Claude Sonnet 5 free?
- You can try Claude Sonnet 5 for free. It is on every Endless plan, including Free, which gives you 100 credits when you create a workspace and 50 credits every week. Each run spends credits from that balance.
- How much does Claude Sonnet 5 cost?
- In Endless it costs 243 credits per 1M input tokens and 1215 per 1M output tokens, on every plan.
- How do I use Claude Sonnet 5?
- Start a chat in your Endless workspace and choose Claude Sonnet 5 in the model picker. Endless can also pick the best model for each message on its own.
- What are the alternatives to Claude Sonnet 5?
- Similar models you can use in Endless include Claude Opus 5.5, Claude Fable 5, and Claude Fable 5.1. Each one has its own page with its price and plan.
- How does Claude Sonnet 5 compare with Claude Opus 4.8?
- Sonnet 5 performs close to Opus 4.8 and can match it on some tasks at higher effort settings. Opus 4.8 stays ahead on others.
- Should I use Claude Sonnet 5 or Claude Sonnet 5.5?
- Sonnet 5.5 is newer, faster and stronger at agentic coding, so it is the default for new work. Sonnet 5 is useful when you want consistency with earlier results.
How to use Claude Sonnet 5 in Endless
- 01
Open a chat
Start a chat in your workspace and choose Claude Sonnet 5 in the model picker.
- 02
Bring your context
Attach files, mention a project with @, or ask it to search the web and social media.
- 03
Turn answers into work
Generate images and video, write documents and save what matters to a project.
Related models
Claude Opus 5.5
by Anthropic
Long agentic coding and research work over a 1M-token context
324 / 1620 credits per 1M tokens
Claude Fable 5
by Anthropic
Long autonomous sessions that stay focused across millions of tokens
810 / 4050 credits per 1M tokens
Claude Fable 5.1
by Anthropic
Hard reasoning and long unattended agent runs over a 1M-token context
810 / 4050 credits per 1M tokens
Give your next idea a place to grow.
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