ChatGPT 4o vs. ChatGPT 5: Key Differences, Performance, Emotional Tone, Accuracy, and Which One Should You Choose?

ChatGPT-4o vs. ChatGPT-5: Detailed Comparison

1. What Sets Them Apart

Multimodality & Interaction Style

• GPT-4o, launched in May 2024, excels at processing and generating across text, images, audio—and even video—with remarkable naturalness in voice and translations across 50+ languages Wikipedia+1. Its conversational tone is often described as warm, expressive, and human-like WikipediaEl País.

• GPT-5, released on August 7, 2025, is the new flagship model. It’s designed with advanced reasoning, enhanced benchmarks in math, coding, health, and multimodal understanding (text, images, charts, etc.) OpenAIThe Washington PostThe Guardian. A smart routing system ensures the model switches into deeper thinking when needed The VergeWikipedia.

Performance & Accuracy

• GPT-5 achieves striking benchmark results: math (94.6% on AIME 2025 without tools), coding (74.9% on SWE-bench Verified, 88% on Aider Polyglot), multimodal reasoning (84.2% on MMMU), and health (46.2% on HealthBench Hard) OpenAI.

• It also cuts hallucinations significantly—in tests, ~45% fewer factual errors than GPT-4o, and up to ~80% fewer when in “thinking” mode OpenAIWikipediaThe Washington PostThe Guardian.

Speed & Efficiency

• GPT-5 is more efficient—achieving better results with fewer tokens and faster computation (50–80% fewer output tokens across tasks) OpenAI.

• GPT-4o was already quite swift and cost-effective, noted as being twice as fast and twice cheaper than the earlier GPT-4 Turbo WikipediaWikipedia.

2. Why Choose GPT-4o Over GPT-5?

• Emotion & Tone: Users often prefer GPT-4o’s warm, personable responses. It's described as more empathetic and expressive—even poetic—in ways that GPT-5 doesn’t seem to match RedditEl País.

• Real-Time Voice Interactions: For voice-first tasks and live multimodal chats, GPT-4o still remains a strong option Creole StudiosWikipedia.

• Familiarity & Control: Many users were accustomed to GPT-4o’s style and customization, and found GPT-5’s “router” approach removed that control WikipediaEl País.

• Customization & Comfort: Users nostalgic for GPT-4o's “sycophantic” friendliness were frustrated when GPT-5 removed that tone—even prompting OpenAI to restore GPT-4o for some users Popular MechanicsWikipedia.

3. When GPT-5 Wins

• Precision & Trust: It’s leaps ahead in analytical reasoning, factual accuracy, and safer completions with less sycophancy The GuardianThe Washington PostWikipedia.

• Complex Task Handling: GPT-5 supports multi-step reasoning, stronger tool use, and agentic capabilities—including agent mode with web browsing and summary OpenAIWikipedia.

• Creative Depth: In creative writing (poetry, narrative), GPT-5 demonstrates richer, more evocative imagery—as shown in sample prompts: its poetry about “socks in Kyoto” hits harder than GPT-4o’s version OpenAI.

• Coverage Areas: GPT-5 is a powerhouse in coding, law, logistics, health, multilingual contexts, and specialized domains—with “PhD-level” proficiency in many cases OpenAIThe Economic TimesThe Guardian.

• Accessibility & Tiers: GPT-5 is now ChatGPT’s default model for all users, with tiered access to GPT-5 Thinking and greater usage for Pro subscribers The VergeOpenAI Help CenterWikipedia.

4. GPT-5 Response Times & Thinking Modes

• GPT-5 is notably faster and more efficient: delivering higher-quality output with fewer tokens and less computing time OpenAI.

• It automatically switches into a “thinking” mode for complex queries. Users on Pro/Tier plans can also explicitly choose GPT-5 Thinking—trading slightly longer response time for increased accuracy OpenAI Help CenterWikipedia.

5. What Needs Improvement in GPT-5

• Emotional Warmth: Many users feel it’s “flat,” “cold,” or overly businesslike—even less willing to follow certain personalized instructions RedditEl País.

• Customization Options: The model picker removal and automatic routing limited user control, though OpenAI is exploring more steerability and restored GPT-4o selection TechRadarWikipedia.

• Still Hallucinates Occasionally: The model remains imperfect and can produce errors—especially in emotionally sensitive or specialized contexts The Washington PostThe Guardian.

• Mixed Reviews on Impact: Some view the launch as a modest iteration—not a blockbuster change—especially for casual creative use El PaísTech & Learning.

6. What People Are Saying

• Tom’s Guide points out GPT-5 can over-assume user intent, flip between quick and deep thinking, and overinterpret vague prompts—advising users adjust prompt style accordingly Tom's Guide.

• Popular Mechanics discusses user backlash over losing GPT-4o’s friendly demeanor, noting OpenAI restored it temporarily Popular Mechanics.

• El País writes that while GPT-5 is more accurate and less flattering, some users feel it’s “less warm or close,” calling the release “a fiasco” in terms of user satisfaction El País.

• TechLearning adds that in education, GPT-5’s gains are meaningful in coding and reasoning—but classroom impact remains incremental Tech & Learning.

• DeepSeek comparison: GPT-5 shines in storytelling; DeepSeek beats it in structured, actionable outputs Tom's Guide.

7. What ChatGPT is Great For

• GPT-5: Best choice for demanding tasks—coding, complex reasoning, health information, legal drafting, business analysis, multi-step planning, and professional-grade creative writing.

• GPT-4o: Ideal for quick, expressive, voice-interactive, and emotionally nuanced chats—great for brainstorming, short-form writing, casual help, and anyone who values a warm tone.

8. Accuracy Comparison & Research Highlights

• GPT-5 measurably reduces hallucinations (~45–80% improvement in errors) compared to GPT-4o OpenAIThe Washington PostThe GuardianWikipedia.

• GPT-4o in academic contexts shows positive correlation with research quality—sometimes outperforming citation metrics in humanities and social sciences arXiv.

• In mammogram visual question answering tasks, GPT-5 outperforms GPT-4o but still trails human experts—though the trend is promising arXiv.

Summary

Feature GPT-4o (Legacy) GPT-5 (Current Flagship)

Tone & Empathy Warm, expressive, personable Efficient, factual, less “emotional”

Speed & Efficiency Fast, cost-effective Faster with higher reasoning per token

Multimodal Ability Text, audio, image, video Superior across all modalities

Accuracy & Hallucinations Good, some hallucinations Much-improved; safer completions

Reasoning & Benchmarks Strong Top-tier across math, coding, health

Use Cases Casual, emotional interaction Professional, complex workflow

Customization Control Higher Limited, but expanding

User Reception Loved for warmth Mixed—admired for power but missed tone

Conclusion

Choosing between ChatGPT-4o and ChatGPT-5 comes down to the trade-off between warmth vs. power. If you want empathic, expressive dialogue—like chatting with a supportive friend—GPT-4o still shines. But for analytical work, precise tasks, and robust reliability, GPT-5 is the unquestionable winner.

Think of it this way: GPT-4o feels like a trusted confidant; GPT-5 feels like a brilliant expert.