LlamaIndex vs OpenAI API
Data framework for LLMs — RAG-first with LlamaCloud + LlamaParse
vs. Frontier models: GPT-5, o-series reasoning, image, audio, embeddings
Pricing tiers
LlamaIndex
OSS (MIT)
MIT-licensed core. Python + TypeScript. Free forever.
$0 base (usage-based)
LlamaCloud — Free
Free tier of LlamaCloud. 1,000 pages/day via LlamaParse. Basic indexing.
Free
LlamaCloud — Paid
Pay-per-page parsing + usage-based indexing. $0.003 per page (Fast mode).
$0 base (usage-based)
LlamaCloud Enterprise
Custom. SSO, SOC2, higher rate limits, private index hosting.
Custom
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
Free-tier quotas head-to-head
Comparing oss on LlamaIndex vs free-tier on OpenAI API.
| Metric | LlamaIndex | OpenAI API |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
LlamaIndex · 16 features
- Agents — Agent patterns: ReAct, function-calling, multi-agent workflows.
- Document Readers — 200+ readers for PDF, web, Google Drive, SharePoint, Notion, S3, Slack.
- Evaluations — Built-in eval framework: faithfulness, context precision/recall.
- LlamaCloud — Managed indexing + retrieval platform. File connectors, auto-chunking, retrieval…
- LlamaExtract — Schema-based structured extraction from unstructured docs.
- LlamaHub — Community marketplace of readers, tools, prompts.
- LlamaParse — Best-in-class PDF + complex document parser. Tables, math, layout preserved.
- Multimodal — Image + text models, image retrieval.
- Node Parsers — Document chunkers: token, sentence, semantic, hierarchical.
- Observability (OpenLLMetry) — OTel-based tracing baked in.
- Property Graph — Graph-based RAG (knowledge graphs from unstructured data).
- Query Engines — Retrieval + response synthesis combos — router, sub-question, tree, etc.
- RAG — End-to-end RAG patterns: ingest → index → retrieve → synthesize.
- Tools — 50+ pre-built tool integrations.
- Vector Store Integrations — 50+ vector DB integrations.
- Workflows — Event-driven agent workflows (AgentWorkflow).
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.
Developer interfaces
| Kind | LlamaIndex | OpenAI API |
|---|---|---|
| SDK | llama-index (Python), llamaindex (TS) | openai-dotnet, openai-go, openai-node, openai-python |
| REST | LlamaCloud API, LlamaParse API | OpenAI REST API |
| MCP | LlamaIndex MCP | OpenAI MCP |
| OTHER | — | Realtime API (WebSocket) |
Staxly is an independent catalog of developer platforms. Outbound links to LlamaIndex and OpenAI API are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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