Claude 2.1
No estimate
No hardware requirements for this model
The weights for this model have not been published, so it cannot be downloaded or run on your own hardware at any size. It is reachable only through its provider, and no graphics card changes that.
On record
Full specification
Everything on record for this model. Most of it describes how it was trained rather than how it runs — useful context for judging how much work went into it, and how it compares with models built at a different scale.
Origin
Who built this model, where, and when it was published.
- Organisation
- Anthropic
- Organisation type
- Industry
- Country
- United States of America
- Published
- 21 November 2023
What it does
The problem areas the model was built for. A model can carry several of each.
- Domain
- Language
- Task
- Language modeling, Chat, Language modeling/generation, Question answering
- Approach
- Reinforcement learning
- Base model
- Claude 2
Size
How large the model is and how much data it was trained on. Parameters are the figure that decides whether it fits on a given graphics card.
- Training data
- tokens
Availability
Whether you can obtain the model and run it on your own hardware, which is what decides if any of the graphics-card figures on this page apply.
- Weights
- Closed — provider access only
- Model access
- API access
- Training code
- Unreleased
How it is classified
Labels the source dataset applies when tracking notable models, and how confident it is in the entry.
- Foundation model
- Yes
- Likely above 10²³ FLOP
- Yes
- Why it is tracked
- Significant use
- Record confidence
- Unknown
Sources
Where this record came from and when it was last checked.
- Reference
- Introducing Claude 2.1
- Last updated
- 28 November 2025
What the numbers mean
What this model is
Claude 2.1 was published by Anthropic, in United States of America, in November 2023. The organisation is categorised as industry.
It works in Language, and is recorded as doing language modeling, Chat, Language modeling/generation, Question answering.
Its starting point was Claude 2 — most models at this scale are adapted from an existing base rather than built from nothing.
Because the weights are not available, none of the hardware figures elsewhere on this site apply to it.
How it was trained
The reason it appears in this catalogue at all is significant use.
Answers
Claude 2.1 — common questions
Is Claude 2.1 open source?
No. Claude 2.1 has not had its weights published, so it exists only as a service controlled by its owner.
How many parameters does Claude 2.1 have?
No parameter count has been published for Claude 2.1, which is why no memory or speed figure appears on this page.
Who created Claude 2.1?
Claude 2.1 was published by Anthropic, based in United States of America, categorised as industry.
When was Claude 2.1 released?
Claude 2.1 was published in November 2023. Capability per parameter has improved considerably since, so a newer model of the same size is often the better use of the same hardware.
What is Claude 2.1 used for?
Claude 2.1 works in Language, and is recorded as handling language modeling, Chat, Language modeling/generation, Question answering. Models frequently carry more than one of each, and the tags describe purpose rather than capability limits.
What GPU do I need to run Claude 2.1?
None. Claude 2.1 is a closed model — its weights were never published, so it cannot be downloaded or run on your own hardware at any price. It is reachable only through its provider.
The other direction
Looking at it from the other side?
This page starts from the model. If you already own a card and want to know everything it will run, start from the hardware instead.