> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ollama.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Context length

Context length is the maximum number of tokens that the model has access to in memory.

<Note>
  Ollama defaults to the following context lengths based on VRAM:

  * \< 24 GiB VRAM: 4k context
  * 24-48 GiB VRAM: 32k context
  * \>= 48 GiB VRAM: 256k context
</Note>

Tasks which require large context like web search, agents, and coding tools should be set to at least 64000 tokens.

## Setting context length

Setting a larger context length will increase the amount of memory required to run a model. Ensure you have enough VRAM available to increase the context length.

Cloud models are set to their maximum context length by default.

### App

Change the slider in the Ollama app under settings to your desired context length.

<img src="https://mintcdn.com/ollama-9269c548/SjntZZpXgbN5v4M5/images/ollama-settings.png?fit=max&auto=format&n=SjntZZpXgbN5v4M5&q=85&s=e8a7ccd30fd9cee5e93662db05b43dc7" alt="Context length in Ollama app" width="2724" height="2570" data-path="images/ollama-settings.png" />

### CLI

If editing the context length for Ollama is not possible, the context length can also be updated when serving Ollama.

```
OLLAMA_CONTEXT_LENGTH=64000 ollama serve
```

### Check allocated context length and model offloading

For best performance, use the maximum context length for a model, and avoid offloading the model to CPU. Verify the split under `PROCESSOR` using `ollama ps`.

```
ollama ps
```

```
NAME             ID              SIZE      PROCESSOR    CONTEXT    UNTIL
gemma3:latest    a2af6cc3eb7f    6.6 GB    100% GPU     65536      2 minutes from now
```