How to reason about model choice — a durable framework, not a spec sheet.
Model Families Cheat Sheet
The specific "best" model changes month to month, so this page is deliberately a framework for reasoning about model choice, not a leaderboard. Treat any concrete capability or price claim here as illustrative and dated; always check the provider's current documentation before committing.
The major families (as of this writing)
| Family / source | Access | Weights | Typical strengths |
|---|---|---|---|
| OpenAI (GPT) | API | Closed | Broad general capability, large ecosystem |
| Anthropic (Claude) | API | Closed | Long context, strong reasoning & coding |
| Google (Gemini) | API | Closed | Long context, multimodal, GCP integration |
| Meta (Llama) | Self-host/API | Open weights | Strong open baseline, on-prem control |
| Mistral | Self-host/API | Open + closed | Efficient open models, some hosted |
| Others (open) | Self-host/API | Open weights | Fast-moving; Qwen, Gemma, and more |
"Open weights" means you can download and run the model yourself; it does not necessarily mean a fully open-source license — check each model's actual license terms for your use case.
Closed (API) vs. open (self-hosted)
CLOSED / API OPEN WEIGHTS / SELF-HOSTED
────────────── ──────────────────────────
+ best frontier capability + full data control (nothing leaves your perimeter)
+ no infra to run + no per-token vendor fee (you pay compute)
+ managed scaling & updates + customize / fine-tune freely
+ built-in safety tooling + no vendor lock-in or deprecation surprises
- data leaves your perimeter - you run the infra (GPUs, ops)
- per-token cost - frontier gap vs. the best closed models (often)
- vendor lock-in / deprecations - you own safety and moderation yourself
A common pragmatic pattern: prototype on a capable API model to validate the product, then move price-sensitive or privacy-sensitive workloads to a smaller or self-hosted model once you know exactly what you need. Running everything locally with a tool like Ollama is also a legitimate default for privacy-first or fully offline projects.
Model sizes within a family
Most providers ship a range from small/fast to large/capable. Pick by task, not by prestige:
- Small / fast / cheap: classification, routing, extraction, simple structured output — high volume, latency-sensitive work. Often a small model with a good prompt beats a large one at a fraction of the cost.
- Mid-size: the workhorse for most RAG answering and general assistant tasks.
- Large / frontier: hard reasoning, complex agents, gnarly coding, ambiguous judgment. Use where capability genuinely pays for the cost.
A useful tactic is routing (see agent architectures): send easy requests to a small model and escalate only the hard ones.
Choosing — the questions that actually matter
- Capability: does it clear the bar on your task? Measure with your own evaluations, not a public benchmark.
- Context length: does your use case (long documents, big RAG contexts, agents) need a large window?
- Cost & latency: per-token price and speed at your expected volume.
- Privacy & data handling: can the data leave your perimeter? What's the retention/training policy? See PII and secrets.
- Deployment: API convenience vs. self-hosted control.
- Structured output / tools: does it support the structured output and tool-calling you need?
- Multimodality: do you need image, audio, or video input?
The honest caveat
This is the fastest-moving part of the whole field. New models, new price cuts, and new capabilities land constantly, and today's ranking is next quarter's footnote. Don't hard-wire your architecture to one model. Keep the model behind an adapter/interface so you can swap it, and let your evaluation harness — not marketing — tell you when a new one is actually better for your task.
Next: Further Reading.