Are sampling parameters still supported on Opus 4.7?

No. Setting temperature, top_p, or top_k to any non-default value on Opus 4.7 returns a 400 error. Omit these parameters and use prompting to guide model behavior.

Claude Models Roadmap May 2026: Opus 4.7, Knowledge Cutoffs, the 1M Context Window, and What's Real About Claude 5

Q: Has Anthropic officially announced Claude 5?

As of May 15, 2026, no Anthropic-published Claude 5 announcement was located on anthropic.com or docs.claude.com. Third-party sources have reported a Q2 2026 launch window, but those specs were not independently confirmed against a primary source.

Q: Is Claude Sonnet 5 a real model I can use?

As of May 15, 2026, Claude Sonnet 5 does not appear in Anthropic's official models overview. The currently available Sonnet is Claude Sonnet 4.6 (model ID claude-sonnet-4-6).

Q: Why does Opus 4.7 use more tokens than Opus 4.6 for the same text?

Opus 4.7 ships with a new tokenizer that contributes to improved performance but uses approximately 1x to 1.35x as many tokens for the same input text compared to previous models.

Last refreshed: May 15, 2026

The pace of new Claude releases in 2026 has been fast enough that the canonical question — “what’s the latest Claude model and what’s it actually good for?” — has a different answer almost every quarter. This article is the current map, dated and sourced, of what Anthropic has shipped in 2026, what’s confirmed about each model’s specs and knowledge cutoffs, and what’s been claimed (but not officially confirmed by Anthropic) about what’s coming next.

Two ground rules first, because the model-roadmap space is full of speculation:

Specs and release dates marked as verified come from Anthropic’s own documentation, news posts, or help center pages. We list the specific source.
Anything marked as reported or claimed comes from third-party reporting (TechCrunch, secondary news sites, analyst commentary) that we could not independently confirm against an Anthropic-published source as of May 15, 2026.

If you’re making product decisions on this information, treat verified facts as actionable and reported facts as directional.

The current generally-available Claude models (May 15, 2026)

From Anthropic’s official models overview and pricing pages, the current production Claude lineup is:

Claude Opus 4.7 — claude-opus-4-7

Status: Generally available, currently the most capable Claude model
Context window: 1 million tokens at standard pricing (no long-context premium)
Max output: 128,000 tokens
Knowledge cutoff: January 2026 (per Anthropic Help Center, verified May 15, 2026)
Pricing: $5/MTok input, $25/MTok output (base rates)
Notable changes from 4.6: New tokenizer (uses up to ~35% more tokens for the same text), high-resolution image support up to 2576px / 3.75MP, new xhigh effort level, task budgets beta. Extended thinking budgets and sampling parameters (temperature, top_p, top_k) are removed.

Claude Opus 4.6 — Still generally available, $5/MTok input, $25/MTok output. Released February 2026.

Claude Sonnet 4.6 — $3/MTok input, $15/MTok output. Includes the 1M token context window at standard pricing.

Claude Haiku 4.5 — Cheapest model in the active lineup at $1/MTok input, $5/MTok output.

Earlier models still active or in deprecation: Opus 4.5, Opus 4.1, Sonnet 4.5, and Haiku 3.5 (retired except on Bedrock and Vertex AI). Opus 4 and Sonnet 4 are listed as deprecated.

Knowledge cutoff dates that actually matter

Per Anthropic’s Help Center article on training-data recency (verified May 15, 2026), the most recent generally-available models have January 2026 knowledge cutoffs. That means:

Anything that happened after January 2026 is outside the model’s training data
For current events, recent product launches, recent legal or regulatory changes, or very recent technical documentation, the model needs to be given the information directly (in the prompt, via web search, or through tool use) — it can’t be relied on to know it
The model still has tools available (web search, code execution, file access) that can access post-cutoff information when explicitly invoked

The practical version: don’t ask Claude what happened last week and expect it to know. Hand it the source material and ask it to analyze, summarize, or work with what you’ve given it.

The 1M token context window — what it actually unlocks

Per Anthropic’s official pricing documentation (verified May 15, 2026), Opus 4.7, Opus 4.6, and Sonnet 4.6 all include the full 1 million token context window at standard pricing. There’s no long-context premium — a 900,000-token request is billed at the same per-token rate as a 9,000-token request.

That’s an enormous practical change from earlier Claude generations. A 1M context window is roughly:

~750,000 words of English text
Most full books or technical specifications in a single context
~8 hours of meeting transcripts at typical density
An entire mid-sized codebase, including most or all source files

Prompt caching and batch processing discounts both apply at standard rates across the full 1M window. For workloads that involve sending the same large document repeatedly with different questions, prompt caching against a 1M context is one of the highest-leverage cost optimizations available in the current Claude lineup.

What’s reported about Claude 5 (and what we cannot independently verify)

Multiple third-party sources reported in early 2026 that Anthropic CEO Dario Amodei confirmed a Q2 2026 launch window for Claude 5 in a TechCrunch interview published February 1, 2026. The same sources cited an internal-roadmap leak suggesting an April 28 target date.

What we can verify as of May 15, 2026:

Anthropic’s official model lineup, news page, and platform documentation list the latest production models as Opus 4.7 and earlier 4.x variants. Anthropic has not, to our review, published an official “Claude 5” launch announcement on its anthropic.com news page or its docs.claude.com release notes as of this date.
The third-party reporting on Claude 5 specifications (500K context window, 20-25% benchmark improvements, ~90%+ on SWE-bench Verified) is widely repeated but, as far as we could verify, is not sourced to an Anthropic-published document.

The honest read: Q2 2026 ends June 30, so if the reported timeline is accurate, an official Claude 5 announcement could plausibly land in the next several weeks. If you’re planning a project that depends on a specific Claude 5 capability, build against current Opus 4.7 first and treat any Claude 5-specific work as speculative until Anthropic publishes official model details.

Claude Sonnet 5 — separate question

Some 2026 third-party reporting refers to “Claude Sonnet 5” launching in early February 2026 under an internal codename. We could not, in our May 15, 2026 review, find this model listed in Anthropic’s official models overview, pricing page, or release notes — only Sonnet 4.6 and earlier Sonnet variants are listed as currently available models. If “Sonnet 5” was a real intermediate release, it does not appear in Anthropic’s current public model documentation under that name.

Two possibilities to consider, neither of which we can confirm: the reported Sonnet 5 may have been folded into the broader 4.x lineup under a different name, or the reporting may have been speculative or premature. If you’re tracking model identifiers for production use, only model IDs published in Anthropic’s documentation (such as claude-opus-4-7, claude-sonnet-4-6, claude-haiku-4-5) are guaranteed to be valid against the API.

How to actually keep up with Claude releases

The signal-to-noise ratio in the model-release coverage space is not great. Two practical sources are reliable enough to bookmark:

Anthropic’s news page at anthropic.com/news — first-party launch announcements with full model details
Claude API release notes at the Help Center release-notes page — concise, dated, version-specific

For breaking changes that affect production code, the Anthropic platform documentation publishes per-version “What’s new” pages (Opus 4.7’s, for example, lists every API breaking change at launch). Those are the canonical reference for migration work.

For everything else — analyst commentary, predictions, leak coverage — treat it as commentary, not as fact.

What this means for your work today

Based on what is verifiable on May 15, 2026:

If you need the most capable Claude model available, use Opus 4.7. It has the largest context window, the highest knowledge cutoff (January 2026), and the strongest reported coding/agentic performance.
If you need cost-efficient production work, use Sonnet 4.6. Same 1M context, much lower per-token rates than Opus.
If you need cheap, fast, simple-task workloads, use Haiku 4.5.
If you’re planning around Claude 5, treat the timing as unconfirmed and build resilience into your code (don’t hard-code model IDs that don’t exist yet).
For knowledge cutoff-sensitive use cases (current events, recent regulatory data, post-January 2026 news), always provide the information directly or use tool calls — don’t rely on training data alone.

Frequently Asked Questions

What is the knowledge cutoff for Claude Opus 4.7?

January 2026, per Anthropic’s Help Center documentation verified May 15, 2026. Information about events, products, or developments after that date is not in the model’s training data and must be provided directly.

What is the largest Claude context window currently available?

1 million tokens, available on Opus 4.7, Opus 4.6, and Sonnet 4.6 at standard pricing with no long-context premium.

Has Anthropic officially announced Claude 5?

As of May 15, 2026, we could not locate an Anthropic-published announcement of a Claude 5 model on anthropic.com or docs.claude.com. Multiple third-party sources have reported a Q2 2026 launch window based on a TechCrunch interview with Dario Amodei, but we could not independently confirm those specifications against a primary source.

Is Claude Sonnet 5 a real model I can use?

As of May 15, 2026, “Claude Sonnet 5” does not appear in Anthropic’s official models overview or pricing documentation. The currently available Sonnet model is Claude Sonnet 4.6 (model ID claude-sonnet-4-6). Earlier reports of a Sonnet 5 release were not confirmed against an Anthropic-published source in our review.

Why does Opus 4.7 use more tokens than Opus 4.6 for the same text?

Opus 4.7 ships with a new tokenizer that contributes to its improved performance but uses approximately 1x to 1.35x as many tokens for the same input text compared to previous models. Anthropic recommends increasing max_tokens headroom and adjusting compaction triggers accordingly.

Are sampling parameters (temperature, top_p, top_k) still supported on Opus 4.7?

No. Setting temperature, top_p, or top_k to any non-default value on Opus 4.7 returns a 400 error. Migration guidance: omit these parameters and use prompting to guide the model’s behavior.

How we sourced this

Sources reviewed May 15, 2026:

Anthropic Pricing Documentation: docs.claude.com/en/docs/about-claude/pricing (primary source for model lineup, per-token rates, context window pricing)
Anthropic Platform Documentation: What’s new in Claude Opus 4.7 (primary source for Opus 4.7 features, breaking changes, tokenizer, image support, task budgets)
Anthropic Help Center: How up-to-date is Claude’s training data? (primary source for knowledge cutoff dates)
Anthropic news page (primary source check for Claude 5 announcement — none located as of May 15, 2026)
Third-party reporting on Claude 5 / Sonnet 5 (TechCrunch interview reports, Claude5.com, Fello AI, WaveSpeed Blog) — cited as reported but not independently confirmed against primary sources

This article applies the verified vs. reported distinction throughout. If any of the unverified third-party claims are confirmed by Anthropic in the weeks after this article’s date stamp, the relevant sections should be updated to reflect the new primary-source documentation.