📏 Embedding Similarity Calculator

Compare two embedding vectors using cosine similarity, dot product, Euclidean distance, magnitudes, and normalized similarity.

✓ Formula shown✓ Worked example✓ Browser-only calculation✓ Updated 2026

Calculate Embedding Similarity

Use comma or whitespace separators.
Both vectors must have the same number of values.

What this embedding similarity calculator calculates

Calculate three common vector-comparison metrics from two comma- or space-separated numeric embeddings.

A similarity threshold is model- and dataset-specific. Calibrate it on labeled relevant and irrelevant pairs rather than copying a universal cutoff.

Embedding Similarity Calculator formula

Cosine similarity = (A·B) ÷ (||A|| × ||B||). Euclidean distance = √Σ(Aᵢ−Bᵢ)².

Assumptions and limitations

The result is an engineering estimate based on the values entered. AI models, tokenizers, runtimes, accelerators, cloud services, and provider billing rules differ. Validate important decisions with measured data from the exact model, hardware, framework, and pricing plan you intend to use.

Worked example

Vectors [1, 0, 1] and [1, 1, 0] have dot product 1 and cosine similarity 0.5.

How to use the result

A similarity threshold is model- and dataset-specific. Calibrate it on labeled relevant and irrelevant pairs rather than copying a universal cutoff.

  1. Start with representative production assumptions rather than best-case demos.
  2. Run a low, expected, and high scenario to understand the range.
  3. Record model version, pricing date, hardware, precision, and workload details.
  4. Replace assumptions with observed p50 and p95 measurements after testing.

Common mistakes to avoid

  • Comparing vectors produced by different embedding models or dimensions.
  • Treating cosine similarity as a calibrated probability.
  • Using raw dot product when vector magnitude varies unexpectedly.

Frequently asked questions

Cosine similarity or Euclidean distance?

Cosine focuses on direction; Euclidean includes absolute distance. The best metric depends on model training and index configuration.

What range does cosine similarity use?

It ranges from −1 to 1, though many embedding distributions occupy a narrower range.

Can I paste large vectors?

Yes within browser limits. The calculation happens locally and requires equal dimensions.

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Methodology and privacy

This educational tool uses the formula and assumptions displayed on the page. Calculations run locally in your browser, and the page does not transmit the values you enter. Results are estimates rather than provider quotes, benchmark guarantees, financial advice, or capacity guarantees. Last methodology review: August 2, 2026.

Formula Explorer connections

Interpretation: cosine similarity compares vector direction, dot product includes magnitude, and Euclidean distance measures geometric separation. Assumption: vectors must come from the same embedding model and dimension; thresholds are model- and dataset-specific.

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