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Decision framework

OpenAI vs Cohere vs Voyage: Which Embedding Model to Choose

TL;DR

Use OpenAI text-embedding-3 (large or small) for general-purpose production retrieval: strong quality, well-supported, reasonable cost, the default choice for most BearPlex engagements. Use Cohere Embed v3 for multilingual workloads or when you want native reranking integration. Use Voyage AI for domain-specific work where their domain-tuned models (voyage-code, voyage-finance, voyage-law) outperform general-purpose models. Use open-source (BGE, E5) for self-hosted requirements. Quality differences between top embedding models on most production tasks are 1-5%: choose based on operational fit (cost, multilingual, sovereignty) rather than chasing benchmark differences.

Side-by-side comparison

DimensionOpenAI text-embedding-3Cohere Embed v3
LicenseClosed source SaaSClosed source SaaS
Quality (general)StrongStrong
MultilingualLimited (English-primary)Strong (100+ languages)
Domain-specific variantsNoNo
Reranking integrationGeneric (any reranker)Native Cohere Rerank
Dimensions1536 / 3072 (Matryoshka truncatable)1024 (also Light variant 384)
Cost (per 1M tokens)$0.02-$0.13$0.10
Enterprise availabilityAzure OpenAIAWS Bedrock
Best forGeneral-purpose, English-primaryMultilingual, with reranking

OpenAI text-embedding-3

Strong general-purpose embeddings, well-supported. The production default.

OpenAI text-embedding-3-large (3072 dims) and text-embedding-3-small (1536 dims) are widely-used production embedding models. Strong quality on general benchmarks; well-supported with extensive ecosystem; reasonable cost; Matryoshka training enables flexible dimension reduction. The default choice for most BearPlex production engagements unless specific requirements (multilingual, domain-specific, sovereignty) point elsewhere.

Pros

  • Strong quality on general benchmarks
  • Well-supported with extensive ecosystem
  • Matryoshka training enables flexible dimensions
  • Reasonable cost
  • OpenAI platform integration
  • Widely tested in production

Cons

  • Limited multilingual coverage compared to Cohere
  • No domain-specific variants
  • Closed source
  • Vendor lock-in to OpenAI

Best for

  • General-purpose production retrieval
  • Teams already on OpenAI platform
  • English-primary workloads

Worst for

  • Multilingual workloads (Cohere stronger)
  • Domain-specific work (Voyage stronger)
  • Self-hosted requirements (open-source needed)
Cost model

$0.13 per 1M tokens (large), $0.02 per 1M tokens (small).

Time to value

Hours from sign-up to first embedding.

Cohere Embed v3

Strong multilingual embeddings. Native reranking integration.

Cohere Embed v3 provides strong production embeddings with excellent multilingual support (100+ languages) and dedicated reranking integration via Cohere Rerank. Strong choice for multilingual workloads or when reranking is part of the retrieval pipeline. Closed-source SaaS (with private deployment options for enterprise).

Pros

  • Excellent multilingual support (100+ languages)
  • Native Cohere Rerank integration
  • Strong production track record
  • Available on AWS Bedrock for enterprise
  • Strong embeddings for English plus other languages

Cons

  • Closed source
  • Smaller ecosystem than OpenAI
  • Per-token cost similar to OpenAI
  • No domain-specific variants

Best for

  • Multilingual production retrieval
  • Pipelines using Cohere Rerank
  • Global SaaS with international customer bases

Worst for

  • English-only workloads where OpenAI is sufficient
  • Domain-specific retrieval (Voyage stronger)
  • Self-hosted requirements
Cost model

$0.10 per 1M tokens.

Time to value

Hours from sign-up to first embedding.

Decision scenarios

Production RAG for English-language B2B SaaS

OpenAI text-embedding-3

OpenAI text-embedding-3. Strong quality, well-supported, reasonable cost. Default choice.

Multilingual customer support across 12 languages

Cohere Embed v3

Cohere Embed v3 multilingual. Quality across 12 languages; pairs well with Cohere Rerank for hybrid retrieval.

Code search across large codebases

Both

Voyage AI voyage-code is the third option here: domain-tuned for code. Worth benchmarking against OpenAI / Cohere on the specific task.

Healthcare client requiring HIPAA-compliant embeddings

Both

Both via enterprise platforms (Azure OpenAI for OpenAI, AWS Bedrock for Cohere) with HIPAA BAA. Sovereign self-hosted (open-source BGE) is the third option.

Healthcare RAG over clinical documents in English

OpenAI text-embedding-3

OpenAI text-embedding-3 (or Voyage's healthcare variants if available). Strong general-purpose quality on English clinical content.

Self-hosted requirement for sovereignty

Both

Neither: open-source BGE (BAAI), E5 (Microsoft), or GTE (Alibaba) for self-hosted requirements.

FAQ

Common questions

Less than people assume between top models. Quality differences on most production benchmarks are 1-5%. The bigger choices are: hybrid vs pure semantic, with vs without reranking, chunking strategy. Embedding model choice matters but often isn't the highest-leverage tuning lever.

Voyage AI is a third major embedding provider with strong domain-tuned variants (voyage-code, voyage-finance, voyage-law). Generally competitive with OpenAI / Cohere on general tasks; often better on in-domain tasks. Worth benchmarking for specialized work.

BGE (BAAI), E5 (Microsoft), GTE (Alibaba), nomic-embed are strong open-source options. Performance approaching managed alternatives on most tasks. Choose for self-hosted / sovereignty requirements or aggressive cost optimization.

Sometimes. Re-embedding 10M documents with OpenAI text-embedding-3-large costs ~$200-500, not prohibitive. A/B test retrieval quality on your eval set before migrating. We migrate clients periodically when quality improvements justify the work.

1536 (OpenAI text-embedding-3-small or text-embedding-3-large truncated) is a strong default. 3072 (text-embedding-3-large full) for highest quality. 384-768 from open-source for cost optimization. Always tune empirically; don't guess.

Voyage AI provides domain-specific variants. They typically outperform general-purpose embeddings on in-domain tasks by 5-15%. Worth using when the workload is heavily concentrated in one domain.

We benchmark on the specific data and use case. Default starting point is OpenAI text-embedding-3 unless requirements (multilingual, domain, sovereignty) point elsewhere. We don't religiously prefer any provider.

Get a recommendation tailored to your situation

BearPlex builds production AI systems using both approaches. We'll tell you which fits your case in a 30-minute scoping call.