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Vector Embedding Calculator

Plan RAG pipeline infrastructure. Estimate memory, storage, and throughput for embedding model and vector index.

Parameters

Quick-start scenarios

Embedding Model

Precision

Corpus / Data

Index / Search

Graph Connections (M)

Connections per node

8
16
32
64

Search Quality (ef_search)

Directly affects query latency and QPS

10
100
500
1k

Infrastructure

Replicas

1
5
10
20

OS/Buffer Overhead (%)

0%
10%
20%
50%
100%

Storage Estimate

Total (all replicas)

768.1 MB

768.1 MB x 1 replica

float32 (4B)
HNSW (graph-based ANN)

100,000
vectors

Raw vectors

585.9 MB

100,000 x 1536d

Index overhead

62.9 MB

HNSW (graph-based ANN)

Metadata

19.1 MB

200B per doc

Est. QPS range

500-5K

~15,000-150,000 active users

Serving tier

In-Memory

Fits in 16 GB RAM

Per replica

768.1 MB

incl. 15% overhead

RAM usage

768.1 MB / 16 GB

4.7% of available RAM

Fits in-memory: lowest-latency search viable

Storage Breakdown

Raw Vectors
Index Overhead
Buffer (15%)

Raw Vectors

585.9 MB

76.3%

Index Overhead

62.9 MB

8.2%

Metadata

19.1 MB

2.5%

Buffer (15%)

100.2 MB

13.0%

Precision / Quantization Trade-offs

Reducing precision cuts memory requirements dramatically. Modern vector DBs support rescoring float32 results from binary/int8 candidates, recovering most recall.

PrecisionBytes/dimMemory vs float32Recall vs float32Notes
float324B100%Baseline (100%)Maximum accuracy
float162B50%~99.9%Negligible loss, recommended default
int8 / scalar1B25%~99%Great for large corpora
binary0.125B3%70-90%Extreme compression, use with re-ranking

Index Type Comparison

Frequently Asked Questions

About These Calculations

Estimates follow standard vector database formulas: HNSW link overhead, IVF centroid memory, PQ codebook sizes, and metadata budgets. A configurable buffer % (default 15%) is applied for OS and framework overhead. QPS ranges are indicative and highly hardware-dependent.