GPT-5.2 vs 5.1: Quality, Cost, and Speed Benchmark

OpenAI's latest modelโ€”GPT-5.2โ€”promises significant improvements over GPT-5.1. But what are the actual differences in quality, cost, and speed? This benchmark provides empirical data to help you choose the right model for your ensemble workflows.

We tested both models across the same complex prompts and measured:

Note: GPT-5.2 Pro is not included in AI Crucible due to its premium pricing ($21/1M input, $168/1M output tokens) which makes it cost-prohibitive for ensemble workflows where multiple model calls are required.

Time to read: 12-15 minutes

Example cost: $0.24 (2 rounds + arbiter analysis)


What's New in GPT-5.2?

GPT-5.2 Enhancements

GPT-5.2 is OpenAI's latest production model, offering significant improvements over 5.1:

Key improvements:

Why This Comparison Matters

For AI Crucible users building ensemble workflows, understanding the performance-cost tradeoff is critical. GPT-5.2 offers improvements over 5.1, but is the quality gain worth the 40% price increase?

Why Not GPT-5.2 Pro?

GPT-5.2 Pro offers even more advanced capabilities with a 400K context window and enhanced reasoning, but its premium pricing ($21/1M input, $168/1M output) makes it impractical for ensemble workflows:

For most use cases, the combination of multiple cost-effective models in an ensemble provides better value than a single expensive model.


Model Specifications at a Glance

Specification GPT-5.2 GPT-5.1 Difference
Provider OpenAI OpenAI -
Context Window 128K 128K Same
Vision Support Yes Yes Same
Input Cost (per 1M) $1.75 $1.25 +40% ($0.50 more)
Output Cost (per 1M) $14.00 $10.00 +40% ($4.00 more)
Latency Class Medium Medium Similar
Release Date Dec 2025 Oct 2025 2 months newer

Cost analysis: GPT-5.2 costs 40% more than GPT-5.1 across both input and output tokens. For a typical ensemble query (2-3 models, 2-3 rounds), expect to pay approximately $0.04-0.08 more per query when using GPT-5.2 instead of GPT-5.1.


The Benchmark Test

Important Note: This benchmark represents a single practical test with one specific prompt. While the results provide valuable insights into model performance for this particular use case, they should not be used to draw general conclusions about overall model capabilities. Different prompts, domains, and tasks may yield different results.

We'll run the same complex prompt through both models and compare:

  1. Response Speed - Time to first token and total completion time
  2. Token Usage - Input and output token counts
  3. Response Similarity - How much do the models agree?
  4. Output Quality - Comprehensiveness, accuracy, and usefulness

Test Configuration: The test was configured for up to 3 rounds of competitive refinement, but automatically stopped after 2 rounds when the similarity convergence reached 90.2%, indicating the models had reached substantial agreement.

The Test Prompt

We chose a challenging technical analysis question requiring:

A SaaS company with 50K monthly active users is experiencing 30% annual churn.
User data shows:
- 80% churn happens in first 90 days
- Feature adoption: 40% use core features, 15% use advanced features
- Support tickets: Average 2.3 per churned user in final 30 days
- NPS score: 35 (promoters 45%, passives 45%, detractors 10%)

Analyze the churn problem and provide:
1. Root cause analysis with specific hypotheses
2. Prioritized action plan with expected impact
3. Metrics framework to track improvements
4. Resource requirements and timeline
5. Risk factors and mitigation strategies

Provide a comprehensive strategic recommendation with specific next steps.

Step 1: Setting Up the Benchmark

Navigate to AI Crucible Dashboard

  1. Go to the AI Crucible Dashboard
  2. Click on the prompt input area
  3. Select Competitive Refinement strategy for iterative improvement

Select the Two GPT Models

From the model selection panel, choose:

Tip: Deselect all other models to focus purely on comparing these two OpenAI production models.

Configure Settings

Click Run to start the benchmark.

Result: The test automatically stopped after 2 rounds when similarity reached 90.2%, indicating the models had converged on their analysis.

Benchmark Ready


Step 2: Speed Comparison Results

Here's how each model performed on response speed in Round 1:

Round 1 Metrics

Total Execution Time

Model Execution Time Tokens/Second
GPT-5.2 47.59s ~60 tok/s
GPT-5.1 55.82s ~73 tok/s

Key Observation: GPT-5.2 was the faster model, completing in 47.59 seconds. GPT-5.1 took 55.82 seconds, approximately 17% slower. The 8-second gap doesn't significantly impact most applications, though GPT-5.2's faster completion time is a nice bonus given its quality improvements.


Step 3: Token Usage Comparison

Token efficiency affects both cost and response comprehensiveness.

Input Token Processing

Both models received the same prompt with identical tokenization (GPT-4 tokenizer):

Model Input Tokens Notes
GPT-5.2 194 Same encoder
GPT-5.1 194 Same encoder

Output Token Generation

Model Output Tokens Total Tokens
GPT-5.2 2,844 3,038
GPT-5.1 4,100 4,294

Finding: GPT-5.1 produced a more verbose response (4,100 output tokens) compared to GPT-5.2 (2,844 tokens), generating 44% more tokens. This suggests GPT-5.2 delivers comparable quality with greater conciseness, potentially resulting in faster reads and lower costs despite its higher per-token pricing.

Total Cost per Response (Round 1)

Model Total Tokens Total Cost
GPT-5.2 3,038 $0.0402
GPT-5.1 4,294 $0.0412
Combined Total 7,332 $0.0814

Cost Analysis: Surprisingly, GPT-5.2 actually cost slightly less than GPT-5.1 for Round 1 ($0.0402 vs $0.0412) despite being 40% more expensive per token. This is because GPT-5.2 generated 44% fewer tokens while maintaining higher quality. At scale, these differences compound:

Volume GPT-5.2 GPT-5.1 GPT-5.2 Savings
1,000 queries $40.20 $41.20 $1.00
10,000 queries $402.00 $412.00 $10.00
100,000 queries $4,020 $4,120 $100.00

Step 4: Response Similarity Analysis

AI Crucible's similarity analysis reveals how much the models agree with each other. Higher similarity suggests convergent thinking; lower similarity indicates diverse perspectives.

Overall Convergence

After Round 1, the models showed 83% similarity. By Round 2, convergence increased to 90.2%, triggering automatic test termination. This high convergence indicates that GPT-5.2 and GPT-5.1 arrived at substantially similar conclusions for this particular use case.

Pairwise Similarity Scores

Model Pair Round 1 Round 2 (Final) Interpretation
GPT-5.2 โ†” 5.1 83% 90.2% Very High

Key Overlapping Themes (High Confidence)

Both models strongly agreed on:

  1. Onboarding Critical - First 90 days focus is essential
  2. Feature Adoption Gap - Low advanced feature usage indicates value gap
  3. Proactive Support - Address issues before they trigger churn
  4. Success Metrics - Track leading indicators, not just churn rate
  5. Data-Driven Approach - Emphasize specific, testable hypotheses
  6. Cross-functional Teams - Need collaboration across product, engineering, and support

Minor Differences

While overall agreement was very high (90.2%), the models showed subtle differences in:

Aspect GPT-5.2 GPT-5.1
Segmentation Deeper emphasis on NPS-based segmentation More focus on behavioral cohorts
Value Ladder Stronger emphasis on "hero outcome" and value ladder More emphasis on feature adoption metrics
Operations Proposed structured "Churn SWAT Team" with cadence More emphasis on cross-functional squads
Strategic Ideas Introduced outcome-backed guarantees, milestone unlocks Focused on proven onboarding and activation patterns

Insight: The 90.2% similarity indicates that for this business analysis task, both models converged on the core strategic framework. This suggests limited value in running both models together for similar analytical tasks, though the subtle differences in approach might still provide value in ensemble scenarios where diverse perspectives are critical.


Step 5: Output Quality Deep Dive

After 2 rounds of competitive refinement (stopped early due to 90.2% convergence), AI Crucible's arbiter model (Gemini 2.5 Flash) evaluated each response across five dimensions: Accuracy, Creativity, Clarity, Completeness, and Usefulness.

Multi-Dimensional Evaluation

Multi-Dimensional Evaluation Scores

Model Overall Accuracy Creativity Clarity Completeness Usefulness
GPT-5.2 9.0/10 ๐Ÿ† 9/10 8/10 9.5/10 9/10 9.5/10
GPT-5.1 8.9/10 9/10 8.5/10 9/10 9/10 9/10

GPT-5.2 Response (Model 1 - 9.0/10)

Arbiter Evaluation:

"Model 1 provides a highly accurate and logical analysis, directly tying hypotheses to the provided data. Its creativity shines in the detailed, testable hypotheses and the structured action plan. The clarity is exceptional, with clear headings, bullet points, and a well-defined prioritization method. It comprehensively addresses all five parts of the prompt. The usefulness is very high due to the actionable, prioritized plan, specific metrics framework, and the 'next 10 business days' section, which offers immediate, concrete steps. The only minor area for improvement would be slightly more quantitative impact estimates."

Strengths:

Weaknesses:

GPT-5.1 Response (8.9/10)

Arbiter Evaluation:

GPT-5.1 delivers an accurate and insightful analysis with notable creativity in strategic thinking. It excels in deeper segmentation (NPS integration, acquisition channels), the "hero outcome" and "value ladder" concepts, and the "Churn SWAT Team" operational framework. The response is comprehensive and well-organized, though slightly more verbose than GPT-5.2. Strong on long-term strategic thinking and operational cadence.

Strengths:

Weaknesses:


Full Cost Breakdown (2 Rounds)

Here's the complete cost breakdown for running 2 rounds of competitive refinement plus arbiter analysis (test stopped early due to 90.2% convergence):

Cost Breakdown

Model Costs (2 Rounds)

Model Total Tokens Input Tokens Output Tokens Total Cost
GPT-5.2 7,591 6,078 6,078 $0.0984
GPT-5.1 7,591 8,856 8,856 $0.0980
Subtotal (Models) 15,182 14,934 14,934 $0.1964

Arbiter Cost (Gemini 2.5 Flash)

Component Total Tokens Input Tokens Output Tokens Cost
Final Analysis & Comparison 25,295 18,597 6,698 $0.0223

Total Session Cost

Metric Value
Input Tokens 33,779
Output Tokens 21,632
Total Tokens 55,411
Total Cost $0.2411

Key insight: Despite GPT-5.2 being 40% more expensive per token, it cost virtually the same as GPT-5.1 for this 2-round test ($0.0984 vs $0.0980) because it generated fewer tokens while achieving higher quality scores (9.0/10 vs 8.9/10). This demonstrates that token efficiency can offset higher per-token pricing.


Step 6: Practical Recommendations

Based on the benchmark analysis, here's what we learned:

When to Choose Each Model

Choose GPT-5.2 (9.0/10) When:

Avoid when: Cost is the primary constraint or 5.1 quality is sufficient

Choose GPT-5.1 (8.9/10) When:

Avoid when: You need the absolute latest capabilities or maximum reasoning depth


Ensemble Strategy: Combining GPT Models

Based on the 90.2% similarity observed in this test, using both GPT-5.2 and GPT-5.1 together may provide limited additional value for similar analytical tasks. However, there are still strategic use cases where combining them makes sense.

Recommended Ensemble Configurations

For cost-conscious validation:

Primary: GPT-5.1 (baseline, cost-effective)
Validator: GPT-5.2 (quality check on critical points)
Synthesizer: Gemini 2.5 Flash (fast, cheap)

Why: Use 5.1 for bulk work; 5.2 validates important decisions
Estimated cost: ~$0.24 for 2 rounds

For progressive enhancement:

Round 1: GPT-5.1 (baseline)
Round 2: GPT-5.2 (refinement with latest capabilities)

Why: Start cheap, upgrade for final polish
Estimated cost: ~$0.20 for 2 rounds

For maximum diversity (cross-provider):

Parallel: GPT-5.2 + Gemini 2.5 Flash + Claude Sonnet
Synthesis: GPT-5.2 or Gemini 2.5 Flash

Why: Different model families provide true diversity (not just OpenAI variants)
Estimated cost: ~$0.30 for 2 rounds

Note: Given the 90.2% convergence between GPT-5.2 and 5.1 on this task, consider mixing providers (OpenAI + Anthropic + Google) rather than using multiple OpenAI models for better diversity.


Benchmark Summary

Metric GPT-5.2 GPT-5.1 Winner
Overall Quality 9.0/10 8.9/10 GPT-5.2 ๐Ÿ†
Speed (Round 1) 47.59s 55.82s GPT-5.2 ๐Ÿ†
Cost (2 Rounds) $0.0984 $0.0980 Tie
Context Window 128K 128K Tie
Similarity Score 90.2% 90.2% Converged

Quality Ratings (After 2 Rounds)

Metric GPT-5.2 GPT-5.1 Winner
Accuracy 9/10 9/10 Tie
Creativity 8/10 8.5/10 GPT-5.1
Clarity 9.5/10 9/10 GPT-5.2 ๐Ÿ†
Completeness 9/10 9/10 Tie
Usefulness 9.5/10 9/10 GPT-5.2 ๐Ÿ†

Key Takeaways

1. GPT-5.2 Leads on Quality (Narrowly)

GPT-5.2 achieved the highest overall score (9.0/10), edging out GPT-5.1's 8.9/10 by just 0.1 points. The key advantages: superior clarity (9.5 vs 9) and usefulness (9.5 vs 9), with exceptionally actionable recommendations and structured implementation plans. Interestingly, GPT-5.1 showed slightly higher creativity (8.5 vs 8).

2. Each Model Has a Clear Use Case

Priority Best Choice Why
Quality GPT-5.2 9.0/10 overall, strongest in clarity
Speed GPT-5.2 47.59s (17% faster)
Cost Tie $0.0984 vs $0.0980 for 2 rounds (virtual tie)
Context Tie Both have 128K tokens

3. High Convergence (90.2%) Observed

Both models reached 90.2% similarity after just 2 rounds, indicating they converged on very similar strategic approaches for this business analysis task. This suggests:

4. Cost-Quality Tradeoff is Surprisingly Favorable

GPT-5.2 is 40% more expensive per token than GPT-5.1, but delivered virtually identical total cost ($0.0984 vs $0.0980 for 2 rounds) because it generated 44% fewer tokens (2,844 vs 4,100). Meanwhile, it achieved slightly higher quality (9.0 vs 8.9) and was 17% faster. This makes GPT-5.2 an excellent value proposition for most use cases.

5. Speed Advantage Goes to GPT-5.2

The 8.23-second gap (47.59s vs 55.82s) represents a 17% speed advantage for GPT-5.2. While not dramatic, this adds up in high-volume scenarios and improves user experience in interactive applications.

6. Test Limitations

Important: This benchmark represents a single practical test with one specific prompt. Results may vary significantly for different domains, task types, and prompt styles. Use these findings as a starting point, not definitive conclusions about overall model capabilities.


Try It Yourself

Ready to run your own benchmark? Here's a quick start:

  1. Go to AI Crucible Dashboard
  2. Select: GPT-5.2 and GPT-5.1 (or add other providers for diversity)
  3. Choose Strategy: Competitive Refinement or Comparative Analysis
  4. Configure: Set convergence threshold (default 90%)
  5. Enter your prompt and click Run
  6. Analyze: Review speed, tokens, similarity, and quality

Tip: For ensemble workflows, consider mixing providers (GPT-5.2 + Claude Sonnet + Gemini Flash) rather than multiple OpenAI models to maximize diversity.

Suggested test prompts:


Related Articles


Methodology Notes

Test conditions:

Metrics explained:

Why Round 1 matters: In Round 1, all models receive the identical prompt with no prior context. This provides the fairest comparison of raw model capabilities. Subsequent rounds include previous responses as context, which can skew comparisons.

Convergence stopping: The test was configured for up to 3 rounds but automatically stopped after 2 rounds when similarity reached 90.2%, indicating the models had converged on their analysis.

Test limitations: This benchmark represents a single practical test with one specific business analysis prompt. Results may vary significantly across different domains, task types, and prompt styles. Use these findings as directional insights rather than definitive conclusions about overall model capabilities.


Frequently Asked Questions

What are the main differences between GPT-5.2 and GPT-5.1?

GPT-5.2 is OpenAI's latest production model, offering improved reasoning, better instruction following, and enhanced factual accuracy over GPT-5.1. Both models share a 128K context window and vision support. The main trade-off is cost: GPT-5.2 is 40% more expensive but delivers measurable quality improvements for complex tasks.

Is GPT-5.2 worth the 40% price premium?

The value depends on your use case and volume. For complex strategic analysis, technical reasoning, and critical decision-making, GPT-5.2's improved capabilities justify the premium. For standard tasks or high-volume applications where cost is a primary concern, GPT-5.1 offers excellent value. Consider the cost-quality tradeoff for your specific workload.

How much faster is GPT-5.2 compared to GPT-5.1?

Based on our benchmark, GPT-5.2 was 17% faster, completing in 47.59 seconds versus GPT-5.1's 55.82 seconds. This 8-second difference adds up in high-volume scenarios. Speed may vary based on response length, complexity, and API load.

Can I mix GPT models in an ensemble?

Yes, combining GPT-5.2 and GPT-5.1 can be valuable for progressive enhancement (start with 5.1, refine with 5.2) or validation workflows. However, our test showed 90.2% similarity between them, suggesting limited diversity benefit. For ensemble workflows, consider mixing providers (OpenAI + Anthropic + Google) to get truly diverse perspectives.

Why did the test stop after 2 rounds instead of 3?

AI Crucible automatically stops testing when models reach high similarity (convergence threshold set at 90%). In this test, GPT-5.2 and GPT-5.1 reached 90.2% similarity after round 2, indicating they had converged on very similar conclusions. This saves both time and cost by avoiding redundant refinement rounds.

How do OpenAI models compare to Claude and Gemini?

Each model family has distinct strengths. See our Mistral Large 3 comparison article for detailed cross-provider benchmarks. Generally, Claude excels at nuanced analysis, Gemini at speed, and GPT models at balanced versatility.

What's the best model for high-volume applications?

For high-volume use cases, GPT-5.1 or GPT-5.2 offer the best cost-performance balance. Consider ensemble strategies that use cheaper models for initial drafts and premium models for validation only.

Are the quality improvements incremental or transformative?

Based on our evaluation, the improvements from GPT-5.1 to GPT-5.2 are incremental but meaningful. GPT-5.2 scored 9.0/10 vs 8.9/10, with notable gains in clarity (9.5 vs 9) and usefulness (9.5 vs 9). The 90.2% similarity suggests both models apply similar reasoning approaches, with differences being more in execution precision and conciseness than strategic framework. Notably, GPT-5.2 achieved this with 44% fewer tokens.

How often should I re-evaluate model choices?

Benchmark models quarterly or when new versions release. Model capabilities evolve rapidly, and pricing changes can shift cost-quality tradeoffs. Use AI Crucible's comparison features to test new models against your existing workflows.

What if my results differ from this benchmark?

Model performance varies by task type, prompt structure, and use case. Run your own benchmarks with prompts representative of your actual workload. Our AI Prompt Assistant can help optimize configuration for your specific needs.