OpenAI API vs Weaviate
Frontier models: GPT-5, o-series reasoning, image, audio, embeddings
vs. Open-source vector DB with hybrid search + modular embeddings
Pricing tiers
OpenAI API
Free Tier (Trial)
$5 free credit for new accounts. Rate-limited.
Free
Pay-as-you-go
No monthly min. Per-token pricing by model.
$0 base (usage-based)
Usage Tiers (1-5)
Automatic tier promotion based on cumulative spend. Higher tiers = higher rate limits + new model access.
$0 base (usage-based)
Enterprise
Custom. Priority access, SLA, dedicated capacity.
Custom
Weaviate
Sandbox (14-day trial)
14-day free trial. Shared cloud cluster. 250 Query Agent req/month.
$0 base (usage-based)
Self-Hosted (OSS)
BSD-3 licensed. Run free on your infra.
$0 base (usage-based)
Flex
From $45/mo pay-as-you-go. Shared HA cluster. 99.5% uptime. 30k Query Agent reqs/mo.
$45/mo
Premium
From $400/mo prepaid. Shared or dedicated. 99.95% uptime. SSO/SAML. Unlimited Query Agent. HIPAA on AWS.
$400/mo
Enterprise
Custom. BYOC / private deployment.
Custom
Free-tier quotas head-to-head
Comparing free-tier on OpenAI API vs sandbox on Weaviate.
| Metric | OpenAI API | Weaviate |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
OpenAI API · 12 features
- Assistants API — Stateful assistants with tools, threads, file search.
- Batch API — 50% discount for async processing within 24h.
- Chat Completions API — Classic /v1/chat/completions endpoint.
- Files API — Upload docs for retrieval, fine-tuning, batch.
- Fine-Tuning — Supervised + DPO fine-tuning for GPT-4o, GPT-4.1, GPT-4o-mini.
- Function Calling — JSON-schema tool calling; parallel calls supported.
- Moderation — Safety classifier API (free).
- Prompt Caching — Auto-cache repeated prefixes; 50% cheaper cached hits.
- Realtime API — WebSocket streaming voice + text with low latency.
- Responses API — Stateful conversational API.
- Structured Outputs — Enforced JSON schema compliance.
- Vision — Image input for GPT models.
Weaviate · 13 features
- Backups — S3, GCS, Azure Blob backup destinations.
- BYOC — Run managed Weaviate in your own cloud account.
- Compression (PQ/BQ/RQ) — Reduce vector memory footprint by up to 32x.
- Dynamic Indexing — HNSW + flat + dynamic index selection.
- Generative Search — Search + RAG answers in one API call.
- Hybrid Search — Combine BM25 + dense vector search in one query.
- Modular Vectorizers — 60+ plug-in vectorizers + generative AI modules.
- Multi-Tenancy — Per-tenant isolated vector stores in one cluster.
- Query Agent (AI) — Agentic natural-language query generator.
- RBAC — Role-based access control for collections + tenants.
- Replication — Multi-node async + sync replication.
- Self-Host (OSS) — BSD-3 licensed. Docker + k8s Helm.
- Structured Filters — Metadata filters pre + post vector search.
Developer interfaces
| Kind | OpenAI API | Weaviate |
|---|---|---|
| SDK | openai-dotnet, openai-go, openai-node, openai-python | weaviate-client, weaviate-go-client, weaviate-java-client, weaviate-ts-client |
| REST | OpenAI REST API | Weaviate REST API |
| GRAPHQL | — | Weaviate GraphQL |
| MCP | OpenAI MCP | Weaviate MCP |
| OTHER | Realtime API (WebSocket) | Weaviate gRPC |
Staxly is an independent catalog of developer platforms. Outbound links to OpenAI API and Weaviate are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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