ERNIE 5.1

By price, ERNIE 5.1 ranks 30th cheapest of 68 on input and 37th on output. Its quality score of 90 ranks 21st of 68, and on value (quality score ÷ output price) it ranks 35th of 68. Its blended rate sits 60% below the catalog average.

In real billing terms: a support chatbot handling 50,000 turns a month (2,000 input / 500 output tokens each) costs about $125 per month on ERNIE 5.1, while a RAG workload of 20,000 queries (8,000 input / 800 output tokens each) runs about $137. Because output is priced 4.5× input here, long-generation tasks scale cost fastest — cap output length before you optimise anything else.

A 128K context window holds roughly 171 pages of A4 text (at ~750 tokens per page), ranking 52nd of 68 here. That covers typical RAG and multi-turn chat, though book-length inputs still need retrieval and chunking. Output runs at about 80 tok/s (46th fastest of 68), acceptable interactively, though long responses will feel slow.

We track 3 Baidu models, and ERNIE 5.1's blended rate sits 30% above that provider's average. If your task tolerates a little less headroom, Hunyuan HY3 (Tencent) blends about 91% cheaper at a quality score of 87, and is worth benchmarking first. Going the other way, qwen3.5 scores 91 on quality for about 90% less.

The closest model in Baidu's line-up is ERNIE 4.5 ($0.55 input / $2.20 output, quality 84). Against it, ERNIE 5.1 scores 6 points higher on quality, runs 10 tok/s slower (about 11%), costs 13% more blended. When two models sit this close on price, the deciding factor is usually the quality ceiling — run both against your real prompts before picking.