binary.md

(embeddings-binary)=

Binary embedding formats

The default output format of the llm embed command is a JSON array of floating point numbers.

LLM stores embeddings in a more space-efficient format: little-endian binary sequences of 32-bit floating point numbers, each represented using 4 bytes.

The following Python functions can be used to convert between the two formats:

import struct

def encode(values):
    return struct.pack("<" + "f" * len(values), *values)

def decode(binary):
    return struct.unpack("<" + "f" * (len(binary) // 4), binary)

When using llm embed directly, the default output format is JSON.

Use --format blob for the binary output, --format hex for that binary output as hexadecimal and --format base64 for that binary output encoded using base64.