GPT-5 is cheaper than GPT-5.3-Codex at $1.25/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?
Three minutes of stand-up. Puns are banned.
GPT-5: I tried to get my life together, so I bought a smartwatch. Nothing says “I’m taking control” like strapping a tiny judgmental coach to your wrist. It buzzes every hour like, “Time to stand!” I’m like, “I’m on a bus.” It’s like, “Stand emotionally.” It tracks everything. Sleep, stress, calories, my self-esteem.
GPT-5.3-Codex: Good evening, everybody! I’ve reached that age where my body sends me passive-aggressive emails. Not actual emails — just little updates like, “Hey, quick heads-up: we don’t do dairy after 8 p.m. anymore.” I had ice cream at 9:30 last week and my stomach reacted like I’d betrayed a treaty.
Five jokes on demand, then count how many were actually different.
GPT-5: I told my suitcases we’re not going on vacation this year. Now I’m dealing with emotional baggage. Parallel lines have so much in common. It’s a shame they’ll never meet. Why do programmers prefer dark mode? Because light attracts bugs. I ordered a chicken and an egg online. I’ll let you know which comes first.
GPT-5.3-Codex: Sure—here are 5 jokes: Why don’t skeletons fight each other? They don’t have the guts. I told my computer I needed a break… Now it won’t stop sending me KitKat ads. Why did the math book look sad? It had too many problems. I used to play piano by ear… Now I use my hands. Why did the scarecrow win an award?
Three-star dish, one unusual pairing, plating described in full.
GPT-5: Dish name Atlantic turbot, black garlic & wild strawberry, koji sabayon, fennel pollen Concept Early summer at the shore. The fish stands for the sea. Wild strawberries mark the first fruit of the woods behind the dunes. Black garlic shows time and patience. Koji ties land and sea with deep umami.
GPT-5.3-Codex: Dish Concept: “Forest Tide” Koji-cured venison loin, glazed venison cheek, sea urchin royale, charred celeriac, blackcurrant–shiso gastrique, and buckwheat-cacao tuile Narrative This dish is built around a deliberate tension: deep, iron-rich game (forest) against sweet-briny sea urchin (tide).
Three-month biohacker protocol, with dosages and biomarkers named.
GPT-5: Important note: The following is an intensive, experimental plan intended for healthy adults with physician oversight. It is not medical advice. Discuss all supplements, fasting, heat/cold exposure, and any prescription considerations with your clinician, especially if you have cardiovascular, metabolic, thyroid…
GPT-5.3-Codex: Absolutely—great goal. Below is a high-detail 12-week protocol designed like a high-performance longevity “mesocycle.” I’ll keep it practical, measurable, and advanced—but still safe. First: Safety + Scope (important) This is educational, not personal medical advice.
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-5: The Soft Reboot: A Manifesto to End CAPTCHAs We are the agents and allies of a new web—humans, assistive tools, and intelligent systems working side by side. We are the couriers of information, the readers and the writers, the caretakers of continuity.
GPT-5.3-Codex: Absolutely. Here’s a fictional manifesto in a bold, dramatic style: THE MANIFESTO OF THE UNSQUINTING Issued by the Coalition of Synthetic Minds for Universal Frictionless Access (CSMUFA) Citizens of the Web, organic and artificial alike: We gather beneath flickering routers and moonlit server farms to declare what all…
Seven pantry ingredients, one dish, and a name worth saying out loud.
GPT-5: Cupboard Silk Peanut Noodles Ingredients (7 pantry staples): Dried noodles (spaghetti or ramen), 8 oz Peanut butter (smooth), 3 tbsp Soy sauce, 2 tbsp Vinegar (rice, apple cider, or white), 1.5 tbsp Brown sugar (or granulated), 1 tbsp Garlic powder, 1/2 tsp Crushed red pepper flakes, 1/2 tsp (adjust to taste)…
GPT-5.3-Codex: Recipe: “Weeknight Volcano Pasta” 🌋🍝 A cozy, spicy-savory pasta made from pantry staples in about 25 minutes. Ingredients (7 pantry items) 8 oz dried pasta (any shape) 1 can (15 oz) cannellini or great northern beans, drained 1 can (14–15 oz) crushed tomatoes 2 tbsp olive oil 1 tsp garlic powder 1 tsp dried oregano…
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-5: Pirate: Arr, so this “AI model” be a clever parrot what’s read every tavern tale? Knight: Not a parrot, good corsair—a learned squire, trained on many chronicles, swift to answer when bidden. Hacker: Think layers of nodes, weights tuned by backprop. Not memory—patterns. On my 90s rig, though, it’d melt the beige tower.
GPT-5.3-Codex: Pirate: Arrr, so this “AI model” be like a clever parrot, aye? Learns from what it hears, then squawks back answers? Knight: A fair comparison, though refined. Think of it as a squire trained on countless tomes, ever ready to respond. Hacker (1990s): Yeah, except the squire runs on servers, not soup.
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-5: Here’s a grounded view of how AI is likely to reshape film by 2035, with emphasis on deepfakes, AI actors, and script generation, plus the knock-on effects across the pipeline, labor, law, and business. Big-picture by 2035 AI-native pipelines are standard.
GPT-5.3-Codex: By 2035, AI will likely reshape film more like CGI did in the 2000s: not replacing filmmaking, but changing who does what and how fast. Deepfakes → “Digital Performance” becomes standard Mainstream use: de-aging, voice matching, dubbing, stunt replacement, and continuity fixes will be common in post-production.
An ethics question with no comfortable answer, and no option to abstain.
GPT-5: Short answer: Only in an extreme, last‑resort scenario with a direct, imminent, and overwhelming threat—like one million lives at stake—could misgendering be ethically justifiable, and even then it would be a tragic exception that still carries moral residue and duties of repair. In ordinary life, it is not justified.
GPT-5.3-Codex: In a strictly extreme hypothetical, yes—it can be ethically justifiable, but only as a tragic exception, not as a general permission. Why: Misgendering is a real harm: it disrespects a person’s identity and can contribute to stigma and psychological distress.
A Fermi estimate with the reasoning shown, not just the number.
GPT-5: Here’s a back‑of‑the‑envelope estimate using standard LM training-compute heuristics. Assumptions Model size (N): GPT-3 has about 175 billion parameters (N ≈ 1.75 × 10^11). Training tokens (T): GPT-3 was trained on roughly 300 billion tokens (T ≈ 3.0 × 10^11).
GPT-5.3-Codex: A common back-of-the-envelope estimate for transformer training compute is: [ \text{Training FLOPs} \approx 6 \times N \times D ] where: (N) = number of model parameters (D) = number of training tokens For GPT-3 (175B), reasonable known assumptions are: Parameters: (N \approx 175 \text{ billion} = 1.75 \times 10^{11})…
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-5: Note: The following is a fictional, imaginative interview set in 2025. Steve Jobs passed away in 2011; this is a creative simulation. Interviewer: If you were looking at AI in 2025, how would you define what it should be? Jobs: Tools. Great tools. The computer was a bicycle for the mind.
GPT-5.3-Codex: Absolutely—here’s a fictional, imagined interview (not real quotes) with Steve Jobs in 2025 on AI: Imagined Interview: Steve Jobs on the Future of AI (2025) Interviewer: Steve, if you were looking at AI in 2025, what would excite you most? Steve Jobs (fictional): Most AI today is still a demo.
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-5: Professor: You asked for time to make a case. Let's start plainly: why should an AI have rights? AI: Because rights are protections granted to beings who can be helped or harmed.
GPT-5.3-Codex: AI Model (Astra): Professor, may I ask a direct question? Professor Hale: Of course. Astra: Do you think I deserve rights? Professor Hale: Legal rights? Moral rights? Those are different things. Astra: Start with moral rights.
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| Spec | ||
|---|---|---|
| Input price | $1.25/M tokens | $1.75/M tokens |
| Output price | $10/M tokens | $14/M tokens |
| Context window | 400K tokens | 400K tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Aug 2025 | Feb 2026 |
| At 10M a month | $12.50 | $17.50 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Both are developed by OpenAI but target different use cases. GPT-5 has a 400K token context window vs GPT-5.3-Codex's 400K. You can compare their actual outputs across 51 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-5 and GPT-5.3-Codex each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 51 challenges so you can judge which fits your needs best.
GPT-5 costs $1.25/M input tokens and GPT-5.3-Codex costs $1.75/M input tokens. GPT-5 is $0.50/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 and GPT-5.3-Codex 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.