Best LLM API for Chatbots
Find the best LLM API for chatbots and conversational AI. Models ranked by human conversation preference (LMArena Elo), with verified pricing for dialogue, customer support, and interactive assistants.
MODELPRICEWATCH.COM · 2026-09-22
Cost calculator for this use casemonthly cost, top 3 models
- 1 GPT-5.5 Pro
- $—
- 2 Claude Fable 5
- $—
- 3 Muse Spark 1.2
- $—
Full ranking — top 24 models
list prices, USD per 1M tokens| Model | LMArena Elo | Blended* | Input | Output | Context | Provider |
|---|---|---|---|---|---|---|
| 1GPT-5.5 Pro | 1510 Elo | $67.50 | $30.00 | $180.00 | 1M | OpenAI |
| 2Claude Fable 5 | 1506 Elo | $20.00 | $10.00 | $50.00 | 1M | Anthropic |
| 3Muse Spark 1.2 | 1500 Elo | $2.00 | $1.25 | $4.25 | 1M | Meta |
| 4Claude Fable 5.1 | 1499 Elo | $20.00 | $10.00 | $50.00 | 1M | Anthropic |
| 5Claude Opus 4.6 | 1497 Elo | $10.00 | $5.00 | $25.00 | 1M | Anthropic |
| 6Claude Opus 4.7 | 1494 Elo | $10.00 | $5.00 | $25.00 | 1M | Anthropic |
| 7Muse Spark 1.3 | 1493 Elo | $2.00 | $1.25 | $4.25 | 1M | Meta |
| 8Gemini 3.8 Flash | 1493 Elo | $1.50 | $0.750 | $3.75 | 1M | |
| 9Claude Opus 5 | 1493 Elo | $10.00 | $5.00 | $25.00 | 1M | Anthropic |
| 10Muse Spark 1.1 | 1493 Elo | $2.00 | $1.25 | $4.25 | 1M | Meta |
| 11Gemini 3.7 Flash | 1490 Elo | $1.50 | $0.750 | $3.75 | 1M | |
| 12Gemini 3.1 Pro | 1487 Elo | $4.50 | $2.00 | $12.00 | 2M | |
| 13Kimi K3 | 1485 Elo | $6.00 | $3.00 | $15.00 | 1M | Moonshot |
| 14GPT-5.6 Sol | 1484 Elo | $8.00 | $4.00 | $20.00 | 1M | OpenAI |
| 15GLM-5.3 | 1483 Elo | $2.15 | $1.40 | $4.40 | 1M | Z.AI |
| 16Claude Opus 4.8 | 1481 Elo | $10.00 | $5.00 | $25.00 | 1M | Anthropic |
| 17Qwen3.8-Max | 1481 Elo | $3.00 | $2.00 | $6.00 | 1M | Alibaba |
| 18Gemini 3.6 Flash | 1480 Elo | $1.50 | $0.750 | $3.75 | 1M | |
| 19GPT-5.4 Pro | 1478 Elo | $67.50 | $30.00 | $180.00 | 1M | OpenAI |
| 20Gemini 3.5 Flash | 1478 Elo | $3.38 | $1.50 | $9.00 | 1M | |
| 21Hy4 preview | — | $1.25 | $0.834 | $2.50 | 1M | Tencent |
| 22Grok 4.7 | — | $3.00 | $2.00 | $6.00 | 500K | xAI |
| 23Fugu Max | — | $3.00 | $2.00 | $6.00 | 1M | Sakana AI |
| 24Claude Opus 5.5 | — | $8.00 | $4.00 | $20.00 | 1M | Anthropic |
Recent price movement in this ranking
price-only deltas · logged by the daily scan2 of the top 24 chatbot models have re-priced since we began tracking · last checked .
| Model | Changes | Latest move | Provider |
|---|---|---|---|
| GPT-5.6 Sol | 1 | price cut on : $5.00/$30.00 → $4.00/$20.00 /Mtok | OpenAI |
| Gemini 3.6 Flash | 1 | price cut on : $1.50/$7.50 → $0.750/$3.75 /Mtok |
Most recently, GPT-5.6 Sol cut its price on — a sign pricing in this category is still moving, so re-check before committing to a long-term choice. See all recent price moves →
How models are selected
Generally-available conversational models (mid-tier, flagship and fast classes), ranked by LMArena Elo — blind human preference votes on real conversations, independently collected. One row per model — host duplicates are collapsed. Models without an Elo rating rank below rated ones, cheapest first.
Prices are per million tokens (Mtok), sourced directly from — and linked to — official provider pricing pages. "Blended cost" is (3×input + 1×output) ÷ 4 — weighted toward input because real workloads read far more tokens than they generate.