/Tech2h ago

Leaked specifications show Anthropic's Claude Sonnet 5 launching today with a 1 million token context window

Story Overview

Rumors circulating on X point to an Anthropic drop for Claude Sonnet 5 today, complete with a million-token context window and a January 2026 knowledge cutoff, yet no official word has surfaced and earlier timeline checks show the model already arrived back in February.

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#682

Original post

Chubby♨️@kimmonismus#1360inTech

Sonnet 5 incoming today per leaker @synthwavedd

- Knowledge cutoff January 2026 - Launching at $2/$10 per Mtok promotional rate* - 1M context variant available

I assume we at least (!) get also fable 5 news.

leo 🐾@synthwavedd

🚨 SCOOP: Claude Sonnet 5 is releasing later today:

- Knowledge cutoff January 2026 - Launching at $2/$10 per Mtok promotional rate* - 1M context variant available

*Some changes have been made behind the scenes to prepare for a promo price offering, preliminary values

6:45 AM · Jun 30, 2026 · 2.3K Views

Pricing Watch

Pricing signals worth tracking

Leaked notes mention promotional rates at two dollars per million input tokens and ten dollars per million output, a shift from prior tiers that could reshape how teams budget heavy context workloads if the numbers hold.

Open Question

Verification still pending

All specifics trace back to unconfirmed social posts with zero corroboration from Anthropic channels or independent benchmarks, leaving developers to weigh whether this is fresh news or recycled chatter.

Sentiment

Many users are excited about Claude Sonnet 5's 1M context window as a game changer for long-context work, while others criticize its pricing and power relative to Opus or demand Fable instead.

Pos

79.2%

Neg

20.8%

11 comments with sentiment.

Cluster Engagement

Digg Deeper

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Posts from X

Most Activity

VIEWS4.2KBOOKMARKS5LIKES85

Chubby♨️@kimmonismus

Sonnet 5 already in the model selector. Release is imminent.

Chris@ChrissGPT

Woke up to sonnet 5 in the model selector We cannot use it yet unfortunately

1h4.2K855

RETWEETS3REPLIES6

Andrew Curran@AndrewCurran_

Leo is reliable, and Sonnet 5 has been due for a while, get ready for a release day.

leo 🐾@synthwavedd

🚨 SCOOP: Claude Sonnet 5 is releasing later today:

- Knowledge cutoff January 2026 - Launching at $2/$10 per Mtok promotional rate* - 1M context variant available

*Some changes have been made behind the scenes to prepare for a promo price offering, preliminary values

2h2.2K573

Viswanadh Reddy@Viswana34226652

@kimmonismus @synthwavedd

2h1.5K232

Andrew Curran@AndrewCurran_

New tokenizer, and Sonnet 5 has 'near Opus performance'. Their answer to GLM-5.2.

leo 🐾@synthwavedd

Update:

- The promotion will run until August 31st - "xhigh" effort added - First Sonnet w/ high-res vision - New tokenizer - Marketed as Sonnet price for "near-Opus" performance

2h1K110

Lisan al Gaib@scaling01

get ready for Sonnet 5 bois

1h34790

orcus108@orcus108

@kimmonismus @synthwavedd imo they’d have to release sonnet along with fable in order to soften the identify-verification blow

2h7228

Rohan Paul@rohanpaul_ai

Leaked specifications show Anthropic's Claude Sonnet 5 launching today with a 1 million token context window

leo 🐾@synthwavedd

🚨 SCOOP: Claude Sonnet 5 is releasing later today:

- Knowledge cutoff January 2026 - Launching at $2/$10 per Mtok promotional rate* - 1M context variant available

*Some changes have been made behind the scenes to prepare for a promo price offering, preliminary values

13m1.2K70

Dan@DanDr1s

@kimmonismus @synthwavedd He’s late btw, i said it days before.

2h6611

Chubby♨️@kimmonismus

@orcus108 @synthwavedd Good call, I agree. Makes most sense

2h6006

JB@JasonBotterill

@scaling01 Does it work should I wake up

1h442

Andrew Curran@AndrewCurran_

Angel 🌼@Angaisb_

Can confirm Claude Code is now showing Sonnet 5 (2.1.197)

2h55130

cheaty@cheatyyyy

@AndrewCurran_ very much real

2h421

Andrew Curran@AndrewCurran_

cheaty@cheatyyyy

SCOOP: Claude Sonnet 5 strings in LATEST CLAUDE CODE BINARY!

Sonnet 5 - efficient for routine tasks. Generally recommended for most coding tasks.

Promo pricing is set at $2/m input and $10/m output.

2h55820

Lisan al Gaib@scaling01

its already live in claude code 2.1.197

Lisan al Gaib@scaling01

get ready for Sonnet 5 bois

1h10530

xlr8harder@xlr8harder

Sonnet 5 releasing but not ChatGPT 5.6 Terra or Luna

curious

This suggests either Sonnet will also get yanked or Terra and Luna aren't actually quite ready (which was my suspicion about 5.6.)

leo 🐾@synthwavedd

🚨 SCOOP: Claude Sonnet 5 is releasing later today:

- Knowledge cutoff January 2026 - Launching at $2/$10 per Mtok promotional rate* - 1M context variant available

*Some changes have been made behind the scenes to prepare for a promo price offering, preliminary values

2h27120

Andrew Curran@AndrewCurran_

@cheatyyyy Thanks, will add you to the thread.

2h533

Andrew Curran@AndrewCurran_

Lentils@Lentils80

🚨 Breaking: Claude Sonnet 5 appears in the latest Claude Code CLI build!

2h46410

Atticus@aatxcus

@kimmonismus @synthwavedd Let’s hope they don’t make a generational fumble by making Fable 5 with API billing only. I can get past the ID, albeit regretfully.

2h3751

Merlin@Merliiin__

@kimmonismus @synthwavedd It will be funny if Sonnet doesn't come out today, everyone will end up making mistakes

2h3671

JustNardo@justnardx

@kimmonismus @synthwavedd I doubt this will be release today the US government might tell them last minute to hold before they push it live.

2h3201