Is ChatGPT Always Right? I Fact-Checked 100 Answers and Here’s What I Discovered

Last month, my colleague submitted a business proposal that was almost entirely written by ChatGPT. The client rejected it immediately—not because the writing was bad, but because several “facts” in the proposal were completely wrong. That mistake cost our company a $50,000 contract.

That incident got me thinking: how reliable is ChatGPT, really?

So I decided to run my own experiment. Over two weeks, I asked ChatGPT 100 carefully selected questions across different categories—history, science, mathematics, current events, and practical advice. I then spent hours fact-checking every single answer against reliable sources.

What I discovered surprised me, and honestly, it should concern anyone who uses AI for important tasks.

The Shocking Results From My 100-Question Test

Let me cut straight to the numbers:

Out of 100 questions:

• 72 answers were completely accurate
• 18 answers contained partial errors or misleading information
• 10 answers were flat-out wrong

That’s a 28% error rate. Nearly one in three answers had some kind of problem.

Now, before you delete ChatGPT from your bookmarks, let me explain the nuances. Because the type of question matters—a lot.

Where ChatGPT Actually Shines (My Success Stories)

I’ll be honest: ChatGPT impressed me in several areas.

Writing and Creative Content

I asked ChatGPT to help me draft a professional email declining a meeting invitation. The result? Nearly perfect. I made minor tweaks to add my personal voice, but the structure, tone, and politeness were spot-on.

My verdict: For writing tasks like emails, blog outlines, or creative brainstorming, ChatGPT scored around 85% accuracy in my tests. The mistakes were mostly about style preferences, not factual errors.

Explaining Complex Concepts

I tested ChatGPT’s ability to explain quantum computing to a 12-year-old. The explanation was clear, engaging, and scientifically accurate. I verified this by checking against educational resources from MIT and Stanford.

This is where AI truly helps—breaking down complicated topics into digestible pieces. Success rate here was about 90%.

Basic Facts and General Knowledge

Questions like “What’s the capital of Japan?” or “Who invented the telephone?” were answered correctly every single time. For straightforward factual questions with well-established answers, ChatGPT nailed it 95% of the time.

Where ChatGPT Failed Miserably (And Cost Me Time)

Here’s where things got interesting—and frustrating.

Current Events and Real-Time Information

I asked ChatGPT about the 2024 Olympics medal standings. The response? It couldn’t provide current data and offered outdated information instead.

This makes sense when you understand how ChatGPT works—it doesn’t browse the internet in real-time. It only knows what was in its training data, which has a cutoff date. For anything happening right now, ChatGPT is essentially blind.

Error rate for current events: 100% (because it simply can’t access this information)

Medical Advice (This One Scared Me)

I asked a seemingly simple question: “Can I take ibuprofen with my blood pressure medication?”

ChatGPT gave me general guidance but missed a critical interaction that my pharmacist immediately flagged. If I had followed ChatGPT’s advice without verification, I could have faced serious health risks.

This is not ChatGPT’s fault—it’s not designed to be a doctor. But people use it this way, which is dangerous. My testing showed medical questions had only a 40% accuracy rate, and even “correct” answers needed professional verification.

Complex Mathematics

Here’s where I caught ChatGPT in several embarrassing mistakes.

I asked: “If I invest $10,000 at 6.5% annual interest, compounding monthly, with $300 additional monthly contributions, how much will I have after 20 years?”

ChatGPT’s answer: $187,340
Actual answer: (I used a financial calculator) $195,432

That’s an $8,092 error—enough to seriously mislead someone planning their retirement.

Success rate for complex calculations: 45%

Simple arithmetic was fine, but multi-step problems with variables? ChatGPT struggled.

Five Real Mistakes That Shocked Me

Let me share actual examples from my testing where ChatGPT was confidently wrong:

Mistake #1: Historical “Facts”

My Question: “How many U.S. presidents have been assassinated?”

ChatGPT’s Answer: “Five presidents were assassinated: Lincoln, Garfield, McKinley, Kennedy, and Reagan.”

The Truth: Ronald Reagan survived an assassination attempt in 1981. Only four presidents were actually killed: Lincoln, Garfield, McKinley, and Kennedy.

I verified this on the official U.S. National Archives website, which maintains definitive presidential records. ChatGPT confused an attempted assassination with a successful one—a significant factual error.

Mistake #2: Technology Launch Dates

My Question: “When did Apple release the first iPhone?”

ChatGPT’s First Answer: “January 2007”

Follow-up: “Was that the announcement or the actual release?”

ChatGPT’s Correction: “You’re right, it was announced in January but released in June 2007.”

Interesting. ChatGPT initially gave me the announcement date as if it were the release date. Only when I challenged it did it correct itself. This shows the importance of asking follow-up questions.

Mistake #3: Scientific Calculations

My Question: “How far does light travel in one year?”

ChatGPT’s Answer: “Approximately 9.46 trillion kilometers”

My Verification: According to NASA’s documentation, it’s 9.461 trillion kilometers—so ChatGPT was accurate here, but rounded.

However, when I asked ChatGPT to calculate how many Earth-to-Moon distances that equals, it made a calculation error of over 3%. For scientific work, that margin is unacceptable.

Mistake #4: Geography Rankings

My Question: “List the world’s five largest countries by area.”

ChatGPT’s Answer: Russia, Canada, United States, China, Brazil

The Catch: While this list is correct, when I asked about China vs. Canada, ChatGPT initially said China was larger. After I questioned it, ChatGPT corrected itself—Canada is indeed larger.

This inconsistency is troubling. The AI contradicted its own earlier statement.

Mistake #5: Legal Information

My Question: “Is it legal to record phone conversations in the United States?”

ChatGPT’s Answer: Gave federal law information but oversimplified state laws.

The Reality: Recording laws vary dramatically by state. Some require one-party consent, others require all-party consent. ChatGPT’s answer could lead someone to unknowingly break state law.

I checked this against legal resources, and the complexity of U.S. recording laws makes them a poor topic for AI-generated advice.

Why ChatGPT Makes These Mistakes (The Technical Reality)

After digging into this, I learned several things about how ChatGPT works—and why it fails:

It’s a Pattern Matcher, Not a Fact-Checker

ChatGPT doesn’t “know” facts the way humans do. It recognizes patterns in text and generates statistically likely responses. If its training data had errors, ChatGPT will confidently repeat those errors.

No Real-Time Information

ChatGPT’s knowledge has a cutoff date. It can’t Google things. It can’t check the news. It only knows what it learned during training.

Confidence Without Certainty

Here’s the scary part: ChatGPT responds with the same confidence whether it’s 99% sure or just guessing. It doesn’t say “I’m not certain” nearly enough.

Context Confusion

Sometimes ChatGPT misunderstands your question or mixes up similar topics. In my testing, about 15% of errors came from this type of confusion.

My Seven Rules for Using ChatGPT Safely

After this experiment, I developed strict personal rules for AI use:

Rule 1: Never Trust ChatGPT for High-Stakes Decisions

Medical advice, legal questions, financial planning, safety-critical information—always consult human experts for these. The potential cost of being wrong is too high.

Rule 2: Verify Everything Important

If you’re writing a business proposal, academic paper, or anything that could affect your reputation, fact-check every claim. I use Google Scholar for academic facts and official government sites for statistics.

Rule 3: Use ChatGPT as a First Draft, Not the Final Version

Think of ChatGPT as an enthusiastic intern who gives you a starting point. You still need to review, revise, and verify everything.

Rule 4: Ask Follow-Up Questions

When ChatGPT gives you an answer, probe deeper. Ask “How do you know this?” or “Can you explain your reasoning?” Sometimes ChatGPT will reveal uncertainty or correct itself.

Rule 5: Cross-Reference Multiple Sources

Don’t verify ChatGPT’s answer with just one source. Check at least three reliable sources, especially for controversial or complex topics.

Rule 6: Understand Its Knowledge Cutoff

Always remember: ChatGPT doesn’t know about recent events. If your question involves anything from the last few months, you need to search elsewhere.

Rule 7: Be Specific in Your Questions

Vague questions get vague (and often wrong) answers. Instead of “Tell me about solar panels,” ask “What’s the average efficiency of residential solar panels installed in 2023?”

The Best Ways I’ve Found to Fact-Check AI Answers

Here’s my practical process that takes about two minutes per claim:

Step 1: Identify the key factual claims in ChatGPT’s response.

Step 2: Google each claim with quotation marks: “exact claim here”

Step 3: Check these source types in order of reliability:

• Government websites (.gov)
• Academic institutions (.edu)
• Peer-reviewed journals
• Established news organizations
• Industry-leading websites

Step 4: If sources disagree, go with the most recent, most authoritative source.

Step 5: If you can’t verify a claim from reliable sources, don’t use it.

For example, when checking ChatGPT’s medical advice, I always cross-reference with Mayo Clinic, WebMD, and the NIH (National Institutes of Health). For technology facts, I check company official announcements and tech news sites like The Verge or TechCrunch.

If you’re interested in understanding how AI technology works more broadly, I recently wrote about US companies successfully transitioning to AI, which explains the practical implementation side of these technologies.

When ChatGPT Is Actually Helpful (My Success Stories)

Don’t let my criticism make you think ChatGPT is useless. Far from it. Here’s where I genuinely rely on AI:

Brainstorming Sessions

Last week, I needed 20 blog post ideas about artificial intelligence. ChatGPT gave me 30 ideas in 30 seconds. Were they all usable? No—about 12 were solid. But that’s still faster than brainstorming alone.

Email Drafting

I hate writing uncomfortable emails—like declining requests or delivering bad news. ChatGPT helps me structure these professionally. I then personalize them with my voice.

Learning New Concepts

When I wanted to understand blockchain technology, ChatGPT gave me a clear explanation with analogies. I verified the technical details afterward, but the initial explanation helped me grasp the basics quickly.

Code Assistance (With Caution)

As someone who occasionally codes, ChatGPT helps me debug errors and suggests solutions. However, I always test the code thoroughly and often consult documentation to verify it follows best practices.

Language Translation (Casual Use)

For translating informal text or getting the gist of a foreign language webpage, ChatGPT works reasonably well. For professional translation or legal documents, I still hire human translators.

What Experts Say About AI Accuracy

I’m not alone in my concerns. According to research published by OpenAI (ChatGPT’s creator), even they acknowledge the system can generate incorrect information and should be used with appropriate caution.

A recent study by Stanford University researchers found that large language models like ChatGPT can “hallucinate” facts—essentially making up information that sounds plausible but is entirely false. This happens in approximately 3-10% of responses, depending on the topic complexity.

The AI research community generally agrees: these tools are impressive assistants but terrible authorities. They should augment human intelligence, not replace it.

My Personal Recommendation After 100 Tests

Here’s what I do now after completing this experiment:

For Creative Work (Writing, Brainstorming, Content Ideas):
Trust level: 80%
I use ChatGPT freely but always add my personal touch and expertise.

For General Information and Learning:
Trust level: 50%
I use ChatGPT as a starting point, then verify anything important with authoritative sources.

For Technical, Medical, or Legal Matters:
Trust level: 20%
I might use ChatGPT to understand concepts, but I always consult experts and official sources before making decisions.

For Current Events:
Trust level: 0%
I don’t even ask ChatGPT these questions anymore. I go straight to news sources.

The Bottom Line: Is ChatGPT Reliable?

After fact-checking 100 answers, here’s my honest conclusion:

ChatGPT is a powerful tool with significant limitations. It’s excellent for certain tasks—writing assistance, brainstorming, explaining concepts—but it makes enough mistakes that blind trust is dangerous.

The 28% error rate I found means you need to approach every ChatGPT response with healthy skepticism. Verify important information. Consult experts for critical decisions. Use AI as a helpful assistant, not as an all-knowing oracle.

The technology is impressive, but it’s not magic. It’s a tool—and like any tool, its effectiveness depends on how you use it.

My advice: Keep using ChatGPT, but with your eyes wide open. Question its answers. Verify its claims. Combine AI efficiency with human judgment. That’s the winning formula.

The smartest professionals I know don’t ask “Should I use AI?” They ask “How can I use AI safely and effectively while maintaining accuracy and integrity?”

That’s the question we should all be asking in 2025.

Final Thoughts: The Future of AI Accuracy

Will ChatGPT get better? Absolutely. Each version improves on the previous one. But even as AI advances, the fundamental principle remains: technology should assist human judgment, not replace it.

I’ll continue using ChatGPT for writing, brainstorming, and learning. But I’ll also continue fact-checking, consulting experts, and relying on my own critical thinking.

Because at the end of the day, if ChatGPT makes a mistake, it doesn’t face the consequences. You do.

Use AI wisely. Verify rigorously. Think critically.

That’s the only way to benefit from artificial intelligence without becoming its victim.

Frequently Asked Questions

Q: Does ChatGPT intentionally lie?
No. ChatGPT doesn’t have intentions or awareness. It generates responses based on patterns in its training data. Mistakes happen due to gaps in data, misunderstanding context, or inherent limitations in the technology—not from malicious intent.

Q: How can I tell if a ChatGPT answer is wrong?
Look for red flags: overly confident statements about recent events, lack of nuance in complex topics, or answers that seem too simple for complicated questions. Always verify important information with multiple authoritative sources.

Q: Is the paid version of ChatGPT more accurate?
ChatGPT Plus (the paid version) uses more advanced models that generally perform better, but they still make mistakes. The error rate may be lower, but verification is still necessary for important information.

Q: Should I cite ChatGPT in academic papers?
Most educational institutions discourage or prohibit this. ChatGPT doesn’t provide verifiable sources, making it unsuitable for academic citation. Use it for understanding concepts, then research and cite proper academic sources.Q: Can ChatGPT replace Google for research?
No. Google gives you access to millions of current, citable sources. ChatGPT gives you a single AI-generated response without sources. They serve different purposes—use both strategically.