Baidu: ERNIE 4.5 21B A3B Thinking
Baidu • LLM
ERNIE-4.5-21B-A3B-Thinking is Baidu's upgraded lightweight MoE model, refined to boost reasoning depth and quality for top-tier performance in logical puzzles, math, science, coding, text generation, and expert-level academic benchmarks.
Specifications
Context Window
131K tokens
Input Price/1M
$0.07
Output Price/1M
$0.28
Parameters
—
Max Output
66K tokens
Information
- Tool Calling
- ❌ Not supported
- Vision
- ❌ Not supported
- Audio
- ❌ Not supported
Full Analysis: Baidu: ERNIE 4.5 21B A3B Thinking
What is Baidu: ERNIE 4.5 21B A3B Thinking?
Baidu: ERNIE 4.5 21B A3B Thinking is an AI model developed by Baidu, classified as a large language model (LLM). It focuses on text processing and natural language generation. As an open source model, it is available for download, customization, and on-premises deployment. With a context window of 131K tokens, it is suitable for processing long documents such as contracts, books, and complete codebases.
Pricing & Costs in 2026
Baidu: ERNIE 4.5 21B A3B Thinking is usage-based, priced at $0.07/1M input tokens and $0.28/1M output tokens. For context: 1 million tokens is approximately 750,000 words, or about 10 average-length books. At this aggressive price point, it is one of the most cost-effective options on the market, ideal for high-volume applications like chatbots, bulk document analysis, and automation.
Benchmarks & Performance
We don't have detailed benchmark results for Baidu: ERNIE 4.5 21B A3B Thinking yet. Benchmarks are updated weekly as new data becomes available from sources like Artificial Analysis, LM Arena, and LiveBench.
It's important to note that benchmarks measure specific aspects and don't capture the full user experience. Factors like instruction adherence, behavior in long conversations, and real-world task quality vary significantly between models and aren't always reflected in standard scores.
Recommended Use Cases
Baidu: ERNIE 4.5 21B A3B Thinking is suitable for a wide range of AI applications: long document analysis (contracts, legal proceedings, codebases), high-volume chatbots and automated support, complex reasoning, math problem solving, and logical analysis, text generation, summarization, translation, and general assistance.
Comparison with Alternatives
In the 2026 AI model ecosystem, Baidu: ERNIE 4.5 21B A3B Thinking competes directly with similarly capable models. Baidu competes in this segment against OpenAI, Anthropic, Google, and Meta. The choice between models depends on the specific use case, budget, latency requirements, and need for features like multimodality and tool calling.
For a detailed side-by-side comparison, use our comparison tool or check the overall model ranking.
Frequently Asked Questions
What is Baidu: ERNIE 4.5 21B A3B Thinking?
ERNIE-4.5-21B-A3B-Thinking is Baidu's upgraded lightweight MoE model, refined to boost reasoning depth and quality for top-tier performance in logical puzzles, math, science, coding, text generation, and expert-level academic benchmarks.
How much does Baidu: ERNIE 4.5 21B A3B Thinking cost?
Baidu: ERNIE 4.5 21B A3B Thinking costs $0.07/1M input tokens and $0.28/1M output tokens. For heavy usage (e.g., a chatbot handling 100k messages/month), costs can range from $10 to $1,000 depending on volume.
How does Baidu: ERNIE 4.5 21B A3B Thinking compare with other models?
We don't have detailed benchmarks for Baidu: ERNIE 4.5 21B A3B Thinking yet. Check the main benchmark page to compare available models.
Is Baidu: ERNIE 4.5 21B A3B Thinking open source?
Yes, Baidu: ERNIE 4.5 21B A3B Thinking is an open source model. You can deploy it on-premises, customize it via fine-tuning, and maintain full control over your data. Check the official repository for the specific license.
What is Baidu: ERNIE 4.5 21B A3B Thinking best for?
Baidu: ERNIE 4.5 21B A3B Thinking excels at complex reasoning and problem solving. With its large context window, it handles long documents, codebases, and extended conversations.
Last updated: May 15, 2026 • View methodology →