AI & Computing

Vector Embedding Storage Calculator (Vector Database Size)

Enter how many vectors and their dimensions to size a vector database.

Your numbers

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Your results

Total storage (GB)
Total storage (GB)
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Raw vectors (GB)
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Metadata and text (GB)
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Bytes per vector
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Vector Embedding Storage Calculator (Vector Database Size) by TheCalcTools

How the Vector Embedding Storage Calculator (Vector Database Size) works

Each embedding takes dimensions × bytes per number. A million 1,024-dimensional float32 vectors take about 4.1 GB before indexing.

Approximate nearest-neighbour indexes such as HNSW add graph links on top, often 30 to 100% more. Store the source text and metadata too, or keep them elsewhere and store only IDs.

The formula

Storage = vectors × dimensions × bytes × (1 + index overhead) + vectors × metadata bytes

Worked example

Using the default values shown in the calculator:

Number of vectors (chunks)1e+06
Embedding dimensions1024
Precisionfloat32 (4 bytes)
Metadata and text per vector (bytes)1000
Index overhead (e.g. HNSW graph)50 %
  1. 1,000,000 × 1,024 × 4 bytes = 4.10 GB of vectors.
  2. With 50% index overhead and 1 KB of text each: 7.14 GB.

Result:

Total storage (GB)7.14
Raw vectors (GB)4.10
Metadata and text (GB)1.00
Bytes per vector7,144

Frequently asked questions

How can I reduce vector storage?

Use fewer dimensions (some models support shortened embeddings), lower precision (float16, int8 or binary quantisation), or product quantisation in the index.

Sources and further reading

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This calculator gives estimates for information only. Check important results independently before you rely on them. See our disclaimer.