Well, if Sonnet 5 performs as well as Opus 4.5 had been, at a cheaper price, it's still a win even if it's not entirely truthful. ... As a mostly codex user I am genuinely excited for this release. Claude Opus 4.5 is generally more expensive than GPT-5 Codex models, with pricing roughly 3.3x–4.0x higher for input tokens and 2.5x–4.2x higher for output tokens, so a 50% discount for essentially 3~4x faster speed and 1M context and better benchmarks is much appreciated and makes more sense.

Claude Sonnet 5, developed under the internal codename “Fennec,” has officially launched on February 3, 2026, setting new benchmarks for coding AI performance while dramatically reducing costs.

Anthropic will release Claude Sonnet 5 this week, according to many sources. The exact date would be 20260203 since the model name is claude-sonnet-5-20260203.

Claude Sonnet 5 launched Feb 3, 2026. Featuring a 1M context window, $3/1M token pricing, and a record 82.1% SWE-Bench score, it redefines autonomous coding.

Claude Sonnet 5, internally codenamed “Fennec,” is Anthropic's latest mid-tier flagship model released on February 3, 2026. It is the first AI model to officially surpass an 82.1% SWE-bench score, outperforming the more expensive Claude Opus 4.5.

They're waiting for all their competitors to ship before Claude 5. ... This is the release pattern. Sonnet 5 will only ship after a major ChatGPT release

Based on leaked info and industry analysis, Claude 5 (or at least Sonnet 5) is most likely to launch in February or March 2026. A date string 20260203 found in Vertex AI logs suggests a possible early February release, though this might just ...

Claude Sonnet 4.5 — Released Sept 2025.

Claude Sonnet 5 launched on February 3, 2026, driving Anthropic to 67% odds for best model by month-end. Markets remain uncertain on full Claude 5 availability, with 96% pricing no release by Februar…

Leaks over the weekend point to a new Anthropic model branded as Claude Sonnet 5, with an internal date string of February 3, 2026.

Leaks suggest Anthropic could release Claude Sonnet 5 next week, featuring major upgrades, improved coding, and a massive context window.

Coverage from Geeky Gadgets suggests Sonnet 5 could cost roughly half as much as Opus 4.5, while offering faster inference and stronger agent-style capabilities, including improved context retention and multitasking. That positions the model as a direct challenger not just to Anthropic’s own lineup, but also to OpenAI's and Google’s upcoming releases. ... Claude Opus 4.5 arrives.

This market resolves YES if Anthropic publicly releases a model officially named "Claude 5" (including variants like Claude 5 Sonnet or Claude 5 Opus) that is accessible to the general public via API or product before June 1, 2026.

We're retiring the 1M token context window beta for Claude Sonnet 4.5 and Claude Sonnet 4 on April 30, 2026. After that date, requests that include the context-1m-2025-08-07 beta header on these models will return a 400 error.

Are you for real? It's a build timestamp :D Not a release date. ... Bro we get it. Stop spamming this message bro damn. ... Claude Coded: Sonnet 4.5, Claude Code 2.0, and more.

Looks like we have a release-date: Sonnet 5, February 3rd!

Anthropic intends to release Claude Sonnet 5 this week (reports point to February 3, 2026). The new Sonnet release is described as a meaningful jump over the Sonnet 4.5/Opus 4.5 family — promising bigger context windows, stronger multi-modal ...

There is no way someone on their team didn’t have access to 5.3 prior to release. Influencers all over the place did. That is not what happened. ... Can we create a megathread for new model speculation? This is getting ridiculous. ... There's really no point for Anthropic to hold Sonnet 5 longer if they already know that 5.3 is much better. ... beeing better than GPT5.3 should not be such a challenge. COding with Codex compared to Claude Code is like Talking to a lobotomized idot vs a motivated Junir / Senior Dev

Second, insider claims reference a maximum two-week window from the leak date, which would place release at February 15, 2026 at the latest[1][9]. As of February 2, 2026, this window has already partially passed, and no official announcement ...

I don't even know why people thought ... think for 2 seconds, opus 4.5 had the date "20251101" in its name, and it released on november 24th....