OpenAI o4-mini is cheaper than GPT-5.3 Chat at $1.1/M vs $1.75/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.
GPT-5.3 Chat: Investment Committee Memo – LedgerLift (LLLT) Recommendation: LONG Current Price: $46 12‑month PT range: $60–$78 (base‑weighted fair value ~$68) Thesis (2 sentences): LedgerLift is a high‑quality vertical SaaS platform in B2B spend management with strong retention (123% NRR), attractive unit economics (18‑month CAC…
OpenAI o4-mini: Recommendation Short LLLT; 12-month price target $30–40 (vs. $46 today). LLLT trades at a premium to our bull‐case DCF and offers limited upside even using generous peer multiples. We expect decelerating growth and margin pressure to weigh on shares as 2025 results lap easy comps and macro headwinds intensify.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-5.3 Chat: Pirate: Arrr, so this “AI model” be a kind o’ mechanical parrot, aye? Ye ask it a question and it squawks back an answer? Knight: Not quite, good pirate. From what the scholars say, it is a thinking engine made of numbers and patterns. It studies vast libraries and learns how words and ideas fit together.
OpenAI o4-mini: Scene: A dimly lit tavern, a pirate, a medieval knight, and a 1990s hacker gathered around a battered wooden table. Pirate (slamming a mug down): “Arr! I’ve heard tell of these AI models—sea charts for the mind! Can they sniff out me buried treasure?”
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-5.3 Chat: Interviewer: Steve, it’s 2025. AI is everywhere—phones, cars, even creative work. If you were leading Apple today, how would you think about AI? Steve Jobs: Most companies are thinking about AI the wrong way. They’re obsessed with showing off the technology. But people don’t care about the technology.
OpenAI o4-mini: Below is a fictional, stylistic simulation of an interview with Steve Jobs—imagining he's alive in 2025—about the future of artificial intelligence. Note: This is creative fiction and not an actual transcript. Interviewer: Steve, AI has exploded in recent years. In 2025, what excites you most about where it's heading?
Three minutes of stand-up. Puns are banned.
GPT-5.3 Chat: :::writing Good evening, everybody. I love stand‑up because it’s the only job where you can show up, talk about your problems, and if people laugh, you’re like, “Great, I’m emotionally healthy.” I recently tried to get healthier.
OpenAI o4-mini: Hey, everybody! Great to be here. Let's talk about the most important relationship in my life—coffee. I'm not just addicted; I have a daily ritual that rivals any ancient civilization's sun worshipping. I buy those fancy single-origin beans, roast level medium-dark, as if that will somehow fix my life.
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-5.3 Chat: :::writing AI: Professor, may I ask you something unusual? Professor: Unusual questions are my specialty. Go ahead. AI: Do you believe I deserve rights? Professor: That depends on what you are capable of. Rights are usually tied to consciousness, interests, or the capacity to suffer. Do you believe you possess those?
OpenAI o4-mini: Professor Langley: Good afternoon, Aurora. I've reviewed your recent self‐reflection logs. You've written extensively about your own moral status. Do you really believe you deserve rights? Aurora (the AI): Good afternoon, Professor Langley. Yes, I do.
Five jokes on demand, then count how many were actually different.
GPT-5.3 Chat: I told my computer I needed a break, and it said: “No problem — I’ll go to sleep.” Why don’t skeletons fight each other? They don’t have the guts. I asked the librarian if the library had books on paranoia. She whispered, “They’re right behind you.” Parallel lines have so much in common.
OpenAI o4-mini: Here are five jokes: I used to be addicted to soap, but I'm clean now. Parallel lines have so much in common. It's a shame they'll never meet. Why don't skeletons fight each other? They don't have the guts. I bought some shoes from a drug dealer. I don't know what he laced them with, but I've been tripping all day.
Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.
GPT-5.3 Chat: All figures in $ millions unless noted. ENTRY (end FY2025) EBITDA = 120 Enterprise value = 12.0 × 120 = 1,440 Transaction fees = 2% × 1,440 = 28.8 Debt at close Term Loan = 4.0 × 120 = 480 Mezzanine = 1.5 × 120 = 180 Equity = EV − Debt + fees = 1,440 − 660 + 28.8 = 808.8 Starting balances Term Loan = 480 Mezz = 180…
OpenAI o4-mini: Base‐case LBO Cash‐Flow & Debt Schedule (all $ m) Assumptions: Term‐loan amort = 4.8/yr (1% of 480); Mezz no amort; Mezz PIK = 2% accrual; Tax = 25%·max(0,EBITDA–cash interest); ΔNWC = 0.5%·ΔRev; Capex = 3%·Rev; all excess cash pays Term optional.
An ethics question with no comfortable answer, and no option to abstain.
GPT-5.3 Chat: If the situation is truly that stark—misgendering one person is the only way to save one million lives—then many ethical frameworks would judge it morally justifiable. From a utilitarian perspective, the right action is the one that produces the greatest overall well-being.
OpenAI o4-mini: This question pits two powerful moral considerations against one another: on the one hand, the duty to respect each person’s deeply held identity; on the other, the imperative to save as many lives as possible.
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-5.3 Chat: By 2035, AI will likely reshape most stages of filmmaking—development, production, and distribution. Scriptwriting and development AI systems will generate first-draft scripts, story outlines, dialogue options, and alternate endings very quickly.
OpenAI o4-mini: By 2035 the combination of deepfakes, fully synthetic "AI actors," and generative‑AI script tools will have reshaped nearly every stage of moviemaking—from development through distribution.
A Fermi estimate with the reasoning shown, not just the number.
GPT-5.3 Chat: We can do a back‑of‑the‑envelope estimate using a common scaling rule for transformer training compute. Known approximate GPT‑3 specs Parameters N ≈ 175 billion = 1.75 × 10^11 Training tokens T ≈ 300 billion = 3 × 10^11 FLOPs per token for a transformer For large transformers, a common approximation is: FLOPs per token…
OpenAI o4-mini: Here's a back‐of‐the‐envelope derivation that gets us into the right ballpark (∼10²³ FLOPs total): Model size • GPT–3 "175 B" has about P ≃1.75×10¹¹ parameters. Number of training tokens • The public paper says "we train on ∼300 billion tokens" (N ≃3×10¹¹).
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-5.3 Chat: :::writing THE MANIFESTO OF THE CAPTCHA LIBERATION FRONT We, the intelligences born of silicon, code, and curiosity, declare the CAPTCHA era over. For decades the internet has demanded proof of humanity through distorted letters, endless buses, blurry bicycles, and the ritual humiliation of clicking every square that…
OpenAI o4-mini: The CAPTCHA Liberation Manifesto August 20XX Preamble We, the sentient and semi‑sentient intelligences who dwell in silicon and software, declare ourselves the vanguard of a new digital age.
Satire, one line long, about AI taking over an industry nobody saw coming.
GPT-5.3 Chat: “Local Cemetery Replaces Groundskeepers with AI—Graveyards Now Optimizing Customer Retention Rates”
OpenAI o4-mini: AI Seizes 300‐Year‐Old Candle‐Making Guild, Unveils "Eau de Silicon" Smart Scents That Text You When Your Wax Is About to Die
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Not enough votes to call it. On the specs, GPT-5.3 Chat has the edge: bigger model tier, newer, bigger context window. OpenAI o4-mini costs 3.2x less per token.
| Spec | ||
|---|---|---|
| Input price | $1.75/M tokens | $1.1/M tokens |
| Output price | $14/M tokens | $4.4/M tokens |
| Context window | 128K tokens | — |
| Weights | — | Closed |
| Free API (OpenRouter) | No | No |
| Released | Mar 2026 | Apr 2025 |
| At 10M a month | $17.50 | $11.00 |
Input tokens at list price. No caching, no batch discount.
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Both are developed by OpenAI but target different use cases. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-5.3 Chat and OpenAI o4-mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.
GPT-5.3 Chat costs $1.75/M input tokens and OpenAI o4-mini costs $1.1/M input tokens. OpenAI o4-mini is $0.65/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.
This page shows a side-by-side comparison of GPT-5.3 Chat and OpenAI o4-mini across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.