Anthropic just made the 1 million token context window generally available for both Claude Opus 4.6 and Claude Sonnet 4.6. The feature had been in beta, but as of March 13, it works out of the box with no special headers, no waitlist, and no price premium.
To put that in plain terms: 1 million tokens is roughly 3,000 pages of text. You can now drop entire codebases, full legal contracts, or months of meeting transcripts into a single Claude conversation and get answers that account for everything.
No Long-Context Tax
The pricing decision here is the real story. Anthropic is charging the same per-token rate whether you send 9,000 tokens or 900,000. Opus 4.6 stays at $5/$25 per million tokens (input/output), and Sonnet 4.6 at $3/$15. Google's Gemini 2.5 Pro offers a comparable 1M window, but charges 2x rates above 200K tokens. Anthropic is betting that removing pricing friction will drive more usage at longer context lengths.
Rate limits also apply uniformly across the full window. During the beta period, heavy context requests sometimes hit lower throughput caps. That restriction is gone.
6x More Media Per Request
The other significant change: each request now supports up to 600 images or PDF pages, up from the previous 100 limit. For anyone doing document analysis, financial review, or research across large PDF sets, this removes what was a real bottleneck. Processing a 400-page report with embedded charts no longer requires chunking it into multiple requests.
Where It's Available
The 1M context window is live on the Claude API, Microsoft Azure Foundry, and Google Cloud's Vertex AI. Requests over 200K tokens just work automatically. Claude Pro and Max subscribers on claude.ai also get access, though the web interface has its own usage limits separate from API pricing.
For developers already building with Claude, there is nothing to change. Existing API calls that were capped at 200K tokens can now send more without code modifications. The practical impact depends on your use case, but the combination of full-length context with no pricing penalty and 6x media capacity makes Claude significantly more useful for document-heavy workflows that previously required workarounds.