The latest foundation model developed by Baidu. It is a high-performance language model with excellent Chinese language support.
Parameters
8000
Context Window
128K
License
Proprietary
Release Date
2026-04-30
Benchmark Performance
AA Intelligence Index
—
LMArena Elo
—
HLE
—
ARC-AGI-2
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SWE-bench Verified
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GPQA Diamond
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MMLU-Pro
—
LiveCodeBench
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AIME 2025
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MATH-500
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Japanese Language Capability
General multilingual model. Basic Japanese processing is possible, but inferior to specialized models.
API Pricing
API pricing for this model is not yet available
Strengths
Weaknesses
Use Cases
Deep Analysis
Arena Text Elo
1476
#13-14 globally, #1 among Chinese models
Search Arena Elo
1223
#4 globally, #1 in China
Pre-training Cost
~6% of comparable models
vs industry benchmarks
Total Parameters
~8000B
compressed from ERNIE 5.0
Context Window
128K tokens
standard for modern LLMs
API Pricing
0.004元/千tokens (input)
extremely cost-effective
Strengths
- ・Industry-leading cost efficiency with only ~6% training cost of comparable models
- ・Top-tier search and information retrieval capabilities (global top 4 in Search Arena)
- ・Strong agent/tool-calling capabilities surpassing DeepSeek-V4-Pro in benchmarks
Weaknesses
- ・Weak in pure mathematical reasoning and advanced spreadsheet operations
- ・Closed-source model with no local deployment options
- ・API pricing details remain unclear and may change after preview period
Competitor Comparison
| Model | Arena | SWE | GPQA | Price |
|---|---|---|---|---|
| ERNIE 5.1 | 1476 | N/A | 91.0 | 0.004元/千tokens input |
| DeepSeek-V4-Pro | <1476 (not top 20) | N/A | 90.1 | Not publicly disclosed |
| Gemini 3.1 Pro | Top 5 globally | N/A | 94.1 | $12-18/1M tokens (estimated) |
ERNIE 5.1 Preview represents Baidu's latest breakthrough in cost-effective, high-performance large language models. Released in late April 2026, this model demonstrates that world-class performance doesn't require massive computational budgets. By compressing parameters to roughly one-third of its predecessor ERNIE 5.0 while maintaining competitive capabilities, Baidu has created what they call a "price-performance benchmark" for Chinese AI models. The model's standout achievements include topping China's rankings on the LMArena search leaderboard (1223 Elo, global #4) and achieving strong results across knowledge, reasoning, and agent capabilities.
The technical innovation centers on Baidu's "Once-for-All" elastic training framework, which enables simultaneous optimization of multiple model sizes during a single pre-training run. This approach, combined with a separated asynchronous reinforcement learning architecture, achieves remarkable efficiency - reducing pre-training costs to just 6% of comparable models. ERNIE 5.1 shows particular strength in Chinese language tasks, creative writing (approaching Gemini 3.1 Pro levels), and tool-calling/agent capabilities, making it especially valuable for Chinese enterprises and developers.
However, the model isn't without limitations. Independent benchmarks reveal significant gaps in pure mathematical reasoning and complex spreadsheet operations compared to top international models like Gemini and Claude. Additionally, as a closed-source model with uncertain long-term pricing, it may not satisfy developers needing local deployment or transparent costs. Baidu plans a full release at their Create 2026 developer conference in May, where pricing details and potential performance improvements are expected.
Sources
Analysis generated: 2026-07-17