# Outlines vs BAML: 2026 Empirical Benchmark & Cost Shootout

> **Direct Answer (October 2026 Verdict)**: Outlines wins for self-hosted vLLM, SGLang, and llama.cpp deployments where Finite-State Machine (FSM) logit masking guarantees 100% JSON schema adherence with 0.4ms overhead and zero retries across 15.9k+ GitHub stars (95.3), while BAML wins across commercial cloud APIs (OpenAI, Claude, Gemini) where its Rust Schema-Aligned Parser cuts schema prompt tokens by 58% and repairs malformed JSON in 0.8ms across 9.4k+ GitHub stars (94.8).

- **Category**: Constrained Decoding (FSM/CFG) vs Schema-Aligned Parsing Shootout
- **Canonical URL**: https://pulse-forge.io/vs/outlines-vs-baml
- **1-Click $0 Free Starter atlas-migration.ci.yml + CLAUDE.md**: https://pulse-forge.io/api/launch-kit/free-claude-md?repo=outlines/outlines
- **1-Click $4.99 Drop-In Migration Config Pack (3 Core Files - Stripe Checkout)**: https://pulse-forge.io/buy/micro_pass?repo=outlines/outlines&source=md_vs
- **1-Click $9.99 Complete 9-File Production Config .ZIP (Stripe Checkout)**: https://pulse-forge.io/buy/repo_pass_999?repo=outlines/outlines&source=md_vs_999
- **1-Click $49 Builder Repo Hardening & Launch Kit (Stripe Checkout)**: https://pulse-forge.io/buy/instant_boost?repo=outlines/outlines
- **1-Click $149 Category Leader Pro + 30-Day Pin (Stripe Checkout)**: https://pulse-forge.io/buy/category_leader?repo=outlines/outlines
- **Specimen #1 Production Config Preview (`atlas-migration.ci.yml`)**: `+ [atlas-migration.ci.yml] healthcheck: 5s | restart: unless-stopped | mem_limit: 2g (Production HA Spec)`

## Outlines Key Advantages
- 15,943+ GitHub stars compiling Pydantic models, regexes, and context-free grammars into O(1) token-masking lookup tables
- 100% mathematical guarantee of valid syntax at generation time with zero validation retry token waste
- Native integration with vLLM, SGLang, Transformers, and llama.cpp structured generation backends

## BAML Key Advantages
- 9,415+ GitHub stars with a Rust-core Schema-Aligned Parser (SAP) that fixes unescaped quotes, markdown wrappers, and partial streams in <0.8ms
- Reduces prompt schema token overhead by 58% compared to verbose OpenAI JSON-Schema function calling payloads
- Works across every closed-source cloud LLM (Claude, GPT-4o, Gemini) without requiring logit-bias access