Phi-3 Mini (non-reasoning)

Compact, Concise, Costly

Phi-3 Mini (non-reasoning)

Microsoft's Phi-3 Mini Instruct 3.8B offers a compact, open-licensed solution for concise text generation, balancing quick initial responses with notable per-token costs.

3.8B ParametersInstruct Model4k Context WindowOpen LicenseConcise OutputAzure HostedSeptember 2023 Knowledge

Microsoft's Phi-3 Mini Instruct 3.8B emerges as a compact, open-licensed language model designed for efficiency and quick responsiveness. Positioned as a non-reasoning model, it aims to deliver concise outputs, making it a candidate for applications where brevity is paramount. While its small footprint and open availability are attractive, our analysis reveals a nuanced performance profile, particularly concerning its intelligence, speed, and pricing structure on platforms like Microsoft Azure. This model is best understood as a specialized tool, excelling in specific niches rather than a general-purpose powerhouse, with its 4k token context window and knowledge cutoff of September 2023 defining its operational boundaries.

On the Artificial Analysis Intelligence Index, Phi-3 Mini scores 13 out of a possible 22, placing it below the average for comparable models. This indicates that for tasks requiring deeper understanding, complex problem-solving, or nuanced reasoning, Phi-3 Mini may require more intricate prompting or might not be the optimal choice. However, a notable characteristic of its performance during intelligence evaluation was its exceptional conciseness. It generated only 4.0 million tokens to achieve its score, significantly less than the average of 6.7 million tokens. This suggests that while its raw intelligence score is modest, it is remarkably efficient in its output, delivering information with minimal verbosity. This efficiency can be a significant advantage in scenarios where token economy is critical, such as constrained environments or cost-sensitive applications.

Speed metrics for Phi-3 Mini present a mixed picture. With a median output speed of 68 tokens per second on Azure, it falls slightly below the average of 76 tokens per second observed across other models. This slower output generation might impact applications requiring high throughput or real-time, extensive text generation. Conversely, its latency, or Time To First Token (TTFT), is a respectable 0.36 seconds. This low latency ensures that users receive an initial response quickly, enhancing the perceived responsiveness in interactive applications like chatbots or user interfaces. The balance between quick initial feedback and a somewhat slower overall generation rate is a key consideration for developers.

Perhaps the most critical aspect of Phi-3 Mini's profile is its pricing. Hosted on Azure, the model carries a blended price of $0.23 per 1 million tokens (based on a 3:1 input-to-output ratio). Breaking this down, the input token price is $0.13 per 1 million tokens, and the output token price is $0.52 per 1 million tokens. These figures are notably high, especially when compared to the average pricing of many other models, which often hover around significantly lower rates for both input and output. For instance, the input token price is described as 'expensive' relative to an average of $0.00, and the output token price similarly 'expensive' against the same average. This premium pricing, particularly for a model with below-average intelligence and speed, demands careful cost-benefit analysis for any deployment.

In summary, Phi-3 Mini Instruct 3.8B is a model with distinct strengths and weaknesses. Its open license and exceptional conciseness make it appealing for specific use cases where resource efficiency and quick initial responses are prioritized, such as embedded applications, simple data extraction, or brief content generation. However, its below-average intelligence, moderate speed, and particularly high per-token costs necessitate a strategic approach to deployment. Users must weigh the benefits of its compact nature and open availability against its operational expenses and performance limitations, ensuring that its unique profile aligns precisely with the demands of their application.

Scoreboard

Intelligence

13 (#12 / 22 / 3.8 Billion Parameters)

Below average intelligence, but highly concise output requiring fewer tokens for evaluation.
Output speed

68 tokens/s

Slower than average, potentially impacting high-throughput applications.
Input price

$0.13 /M tokens

Significantly expensive for input tokens, especially compared to lower-cost alternatives.
Output price

$0.52 /M tokens

Very expensive for output tokens, making extensive generation costly.
Verbosity signal

4.0M tokens

Extremely concise, generating significantly fewer tokens for intelligence evaluation than average.
Provider latency

0.36 seconds (TTFT)

Good time to first token, indicating quick initial response for interactive use cases.

Technical specifications

Spec Details
Model Name Phi-3 Mini Instruct 3.8B
Owner Microsoft Azure
License Open
Parameters 3.8 Billion
Model Type Small Language Model (SLM), Instruct
Context Window 4k tokens
Knowledge Cutoff September 2023
Intelligence Index Score 13 / 22
Output Speed (Median) 68 tokens/s
Latency (TTFT) 0.36 seconds
Input Token Price $0.13 / 1M tokens
Output Token Price $0.52 / 1M tokens
Blended Price (3:1) $0.23 / 1M tokens
Verbosity (Intelligence Index) 4.0M tokens

What stands out beyond the scoreboard

Where this model wins
  • **Exceptional Conciseness:** Delivers highly compact outputs, reducing overall token usage for specific tasks.
  • **Quick Initial Response:** Low Time To First Token (TTFT) of 0.36 seconds ensures rapid initial feedback in interactive applications.
  • **Open License:** Offers flexibility for deployment and integration into various environments.
  • **Small Footprint:** Its 3.8B parameters make it suitable for resource-constrained environments or edge deployments.
  • **Targeted for Brevity:** Ideal for tasks where short, direct answers are preferred over elaborate explanations.
Where costs sneak up
  • **High Per-Token Pricing:** Both input ($0.13/M) and output ($0.52/M) token prices are significantly above average, leading to high operational costs.
  • **Below-Average Intelligence:** May require more complex prompting, iterative calls, or human oversight for nuanced tasks, increasing token consumption.
  • **Slower Output Speed:** At 68 tokens/s, it's slower than many peers, potentially increasing processing time and cost in high-volume scenarios.
  • **Limited Context Window:** A 4k token context might necessitate more frequent API calls for longer conversations or documents, driving up costs.
  • **Not Cost-Effective for Reasoning:** For tasks demanding deep reasoning, a more intelligent model might be cheaper overall due to fewer required tokens or higher accuracy.

Provider pick

Phi-3 Mini Instruct 3.8B is primarily offered through Microsoft Azure, integrating seamlessly into their cloud ecosystem. While its open license allows for self-hosting, the convenience and managed services of Azure are often the default choice for enterprise users. When considering this model, it's crucial to align its unique performance and cost profile with your application's specific needs.

Priority Pick Why Tradeoff to accept
**Priority** **Pick** **Why** **Tradeoff**
**Concise Output** Phi-3 Mini Proven to generate minimal tokens for intelligence tasks, reducing output overhead. May lack depth for complex or nuanced responses.
**Low Latency (TTFT)** Phi-3 Mini Excellent 0.36s TTFT for quick initial responses in interactive applications. Slower overall output speed might negate initial advantage for long generations.
**Open License Flexibility** Phi-3 Mini Offers the freedom to deploy and customize, though Azure hosting is common. Still expensive on Azure; self-hosting requires significant infrastructure investment.
**Cost-Efficiency (Complex Tasks)** Higher-tier models (e.g., GPT-3.5 Turbo) Better intelligence-to-cost ratio for complex tasks, potentially fewer tokens overall. Higher per-token cost, but potentially fewer calls or higher accuracy.
**High Output Throughput** Faster models (e.g., Claude 3 Haiku) Achieve higher tokens/s for applications requiring rapid, high-volume generation. Potentially different intelligence profile or higher per-token cost.

These recommendations are generalized. Optimal provider choice depends heavily on specific application requirements, existing infrastructure, and budget constraints.

Real workloads cost table

Understanding the real-world cost implications of Phi-3 Mini requires translating its per-token pricing into common application scenarios. Given its high token costs, even seemingly small interactions can accumulate expenses rapidly. Here's an estimation for typical workloads:

Scenario Input Output What it represents Estimated cost
**Scenario** **Input** **Output** **What it represents** **Estimated Cost**
Simple Chatbot Response 50 tokens 100 tokens Basic Q&A, short interactive replies $0.0000585
Text Summarization (Short) 1,000 tokens 200 tokens Condensing a short article or email $0.000234
Code Generation (Small Snippet) 200 tokens 150 tokens Generating a utility function or script $0.000104
Data Extraction (Structured) 300 tokens 50 tokens Extracting specific fields from a document $0.000065
Content Generation (Social Media) 100 tokens 300 tokens Drafting a short social media post $0.000169
Email Draft (Medium) 200 tokens 400 tokens Generating a professional email draft $0.000234

These examples highlight that while individual interactions might seem inexpensive, Phi-3 Mini's high per-token cost means that frequent or high-volume usage can quickly lead to substantial expenses. Cost optimization strategies are crucial for sustainable deployment.

How to control cost (a practical playbook)

Given Phi-3 Mini's premium pricing, strategic cost management is not just advisable, but essential. Implementing a robust cost playbook can significantly mitigate expenses without compromising application functionality. Here are key strategies:

Aggressive Prompt Engineering for Brevity

Leverage Phi-3 Mini's inherent conciseness by explicitly instructing the model to be brief and direct. Every unnecessary token adds to the cost.

  • Use phrases like "Summarize concisely," "Provide only the answer," or "Be brief."
  • Limit the maximum output tokens in your API calls.
  • Experiment with few-shot examples that demonstrate desired brevity.
Pre-processing and Post-processing

Optimize both input and output to ensure only essential tokens are processed or billed.

  • **Input:** Remove irrelevant information from user queries or documents before sending to the model.
  • **Output:** Implement post-processing to trim any extraneous text, boilerplate, or formatting that the model might generate.
  • Use external tools for tasks like keyword extraction or sentiment analysis if they can be done more cheaply.
Strategic Caching and Deduplication

For repetitive queries or common responses, avoid re-generating content by implementing a caching layer.

  • Store frequently requested summaries, answers, or code snippets.
  • Identify and deduplicate similar user inputs to serve cached responses.
  • Consider a time-to-live (TTL) for cached items to balance freshness with cost savings.
Task Segmentation and Model Chaining

Break down complex tasks into smaller, manageable sub-tasks. Use Phi-3 Mini only for the parts where its conciseness and low TTFT are beneficial, and consider other models or deterministic logic for other parts.

  • Use Phi-3 Mini for quick classification or short answer generation.
  • Chain it with a cheaper, more powerful model for deeper reasoning if necessary, or with a deterministic system for structured output.
  • Avoid using Phi-3 Mini for tasks requiring extensive, open-ended generation.
Monitor and Analyze Usage Patterns

Regularly review your API usage and costs to identify unexpected spikes or inefficient patterns.

  • Implement logging for token counts per request.
  • Set up alerts for cost thresholds.
  • Analyze which types of prompts or user interactions lead to the highest token consumption.

FAQ

What is Phi-3 Mini Instruct 3.8B?

Phi-3 Mini Instruct 3.8B is a compact, open-licensed language model developed by Microsoft. It's designed for efficiency and conciseness, particularly for instruct-based tasks, and has a parameter count of 3.8 billion.

How does Phi-3 Mini compare in intelligence?

On the Artificial Analysis Intelligence Index, Phi-3 Mini scores 13 out of 22, placing it below average among comparable models. While not a top performer in raw intelligence, it is exceptionally concise in its outputs, requiring fewer tokens to achieve its score.

Is Phi-3 Mini cost-effective?

Phi-3 Mini has notably high per-token pricing on Azure ($0.13/M input, $0.52/M output). While its conciseness can save tokens, its premium pricing means that for many general-purpose or high-volume tasks, it may not be the most cost-effective option without aggressive optimization.

What are Phi-3 Mini's typical use cases?

It is best suited for scenarios where brevity, quick initial responses, and resource efficiency are critical. This includes simple data extraction, short answer generation, basic chatbot interactions, or deployment in environments with limited computational resources.

What is its context window and knowledge cutoff?

Phi-3 Mini Instruct 3.8B has a context window of 4,000 tokens, meaning it can process and generate text up to that length in a single interaction. Its knowledge cutoff is September 2023, so it does not have information beyond that date.

Who owns and licenses Phi-3 Mini?

Phi-3 Mini is owned by Microsoft Azure. It is released under an open license, providing flexibility for developers to use and potentially self-host the model, although it is commonly accessed via Azure's managed services.

How fast is Phi-3 Mini?

Phi-3 Mini has a median output speed of 68 tokens per second, which is slightly slower than the average for comparable models. However, it boasts a good Time To First Token (TTFT) of 0.36 seconds, ensuring quick initial responses.


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