How to Pick an LLM API
There's no single "best" LLM — there's a best one for hard reasoning, a best one for cheap high-volume work, a best one for coding agents. Below are the chat models worth your integration time in 2026, what each costs, and where it wins. Every model here is callable through one key on LinkModel, so you can route per task instead of committing to one vendor. Prices are per 1M tokens (input / output); verify before budgeting.
The Frontier Tier
- Claude Opus 4.8 ($5 / $25) — Anthropic's flagship; the strongest judgment, agentic coding, and long-horizon reasoning, with 1M context. Full pricing in the Claude Opus API guide.
- GPT-5.5 ($5 / $30) — OpenAI's natively omnimodal flagship with native computer use; leads several coding/knowledge benchmarks. See the GPT API pricing guide.
- Gemini 3.5 Flash (~$1.50 / $9) — frontier-ish intelligence at a fraction of flagship cost; often the best value at the top.
The Value Tier
- DeepSeek V4 Flash ($0.14 / $0.28) — absurdly cheap for its quality, 1M context, 98% cache discount. The default high-volume workhorse. See DeepSeek V4 Flash vs GPT-4o.
- MiniMax M2.7 ($0.30 / $1.20) — open-weight, agent-trained, ~a tenth of flagship price at a 50 on the AA Intelligence Index.
- Gemini 2.5 Flash ($0.30 / $2.50) — reliable general-purpose workhorse.
The Coding & Agent Specialists
- Kimi K2.6 ($0.95 / $4.00) — 1T-param MoE, multimodal, orchestrates up to 300 sub-agents; strong on long-horizon coding and UI-from-screenshot.
- GLM-5.1 (~$1.40 / $4.40) — 8-hour autonomous engineering runs; 3rd on Code Arena. Open-weight.
- DeepSeek V4 Pro (~$0.44 / $0.87 promo) — competition-grade coding (LiveCodeBench 93.5). See DeepSeek Pro vs Flash.
- GPT-5.3-codex — agentic coding, mid-task steering. More in best coding LLM API.
Quick Picks
| Need | Best choice |
|---|---|
| Hardest reasoning | Claude Opus 4.8 / GPT-5.5 |
| Best value at the top | Gemini 3.5 Flash |
| Cheap high-volume | DeepSeek V4 Flash |
| Coding agents | GLM-5.1 / Kimi K2.6 / DeepSeek V4 Pro |
| Long-horizon multi-agent | MiniMax M2.7 / Kimi K2.6 |
| Multimodal input | Kimi K2.6 / Gemini |
The Multi-Model Reality
Most production stacks use several: a cheap default, a premium escalation, a coding specialist. That's the argument for one gateway — model selection by parameter, one bill, provider fallback. On LinkModel the chat request shape is identical across all of them, so switching is a config change. Architecture in build an AI app with multiple models; cost tactics in how to reduce AI API costs.
For the cheapest options specifically, see cheapest LLM API; for the head-to-head of the big four, Claude vs GPT vs Gemini vs DeepSeek; and for the full cross-category rate card, the AI API pricing comparison.
Start free with a $1 credit and benchmark the top few on your own prompts.