Token

The unit a language model reads and writes in: a word, part of a word, or punctuation.

Models never see words directly; text is first cut into tokens. A token can be a whole common word, a piece of a rarer one (“un” plus “believable”), or a single punctuation mark. This is why models are priced and limited in tokens rather than words: a 128,000-token context window is a budget of these pieces, roughly three-quarters as many English words.

Where it mattered in the record

  1. Reflection AI launches Beam

    On 5 October 2026 Reflection AI introduced Beam, its 501B-parameter open-weight model with 23B active parameters and 1M tokens of effective context. Beam stays in final red-teaming; weights will follow this month.

  2. Aleph Alpha releases open-weight model Kolibri

    On 3 October 2026 Aleph Alpha released Kolibri, an English-German mixture-of-experts Transformer with 78.1B total parameters and 3.46B active, under Apache 2.0 on Hugging Face. Context reaches 1M tokens, and Merlin-Arthur withholds answers the context does not support.

  3. Anthropic releases Claude Sonnet 5.5

    On 28 September 2026 Anthropic released Claude Sonnet 5.5 at $2 input and $10 output per million tokens, with 1M-token context and 128K max output. It runs on the Claude Platform, AWS, Google Cloud and Microsoft Foundry, and GitHub added it to Copilot the same day.

  4. Alibaba announces Qwen3.8-Max, its largest model to date

    Alibaba announced Qwen3.8-Max on 3 August 2026 with 2.4 trillion parameters, about 95 billion active at a time through a sparse mixture of experts, a context window up to 1 million tokens, and native text, image and video input. Weights were scheduled to follow a week later.

  5. DeepSeek releases V4-Flash for general availability

    DeepSeek made deepseek-v4-flash generally available on 31 July 2026, reporting that it substantially exceeded the V4-Pro-Preview across nine agent benchmarks on the same architecture, with the gains from further post-training. Pricing held at $0.14 and $0.28 per million tokens.

  6. Anthropic releases Claude Opus 5

    Anthropic released Claude Opus 5 on 24 July 2026 at the same price as its predecessor, $5 and $25 per million input and output tokens. The company reported roughly double Claude Opus 4.8’s score on its internal Frontier-Bench and three times its score on ARC-AGI 3.

  7. Google commits $40 million to the White House Genesis Mission

    Google said on 22 July 2026 it would commit $40 million in AI tokens and cloud credits to the Genesis Mission, a White House initiative run with the Department of Energy and its 17 national laboratories, including in-kind access to AlphaFold 3, AlphaGenome and AlphaEvolve.

  8. Alibaba’s Qwen chief resigns and its AI work is consolidated

    Lin Junyang, head of Alibaba’s Qwen model division, resigned in early March 2026, shortly after the release of Qwen3.5. On 17 March Alibaba formed a new AI unit, Alibaba Token Hub, placing Qwen and related work under chief executive Eddie Wu.

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