Mistral Devstral Medium is cheaper than GPT-5.3-Codex at $0.4/M vs $1.75/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Three minutes of stand-up. Puns are banned.
Mistral Devstral Medium: Ladies and Gentlemen, I'm thrilled to be here tonight. I've been doing some thinking about the differences between men and women. Now, I know what you're thinking, "Oh great, another comedian talking about how men and women are different." But hear me out, because I've got a fresh perspective on this.
GPT-5.3-Codex: Good evening, everybody! I’ve reached that age where my body sends me passive-aggressive emails. Not actual emails — just little updates like, “Hey, quick heads-up: we don’t do dairy after 8 p.m. anymore.” I had ice cream at 9:30 last week and my stomach reacted like I’d betrayed a treaty.
A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.
Mistral Devstral Medium: Weak Claim 1: "Works with any language, any device." Why it's weak: This claim is overly broad and may not be entirely accurate. Different languages have unique structures, and it's unlikely that a single model can achieve high accuracy across all languages without significant training data for each.
GPT-5.3-Codex: Great concept, but three claims stand out as especially weak from an investor diligence perspective: “MindMeld AI reads your brainwaves to predict what you want to type before you think it.” (Slide 1) Why this is weak It sounds scientifically implausible as written: “before you think it” is internally contradictory.
Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.
Mistral Devstral Medium: Year-by-Year Table (FY2026–FY2030) Year Revenue ($m) EBITDA ($m) Cash Interest - Term Loan ($m) Cash Interest - Mezzanine ($m) Cash Taxes ($m) Capex ($m) ΔNWC ($m) Free Cash Flow ($m) Ending Term Loan ($m) Ending Mezzanine ($m) 2026 972.0 136.1 43.2 18.0 14.9 29.2 4.8 26.0 468.0 180.0 2027 1040.4 156.1 42.1 21.6 18.4…
GPT-5.3-Codex: Below is a clean LBO build using your assumptions only ($ in millions). Entry math (end FY2025) EV = (12.0 \times 120 = 1,440.0) Fees = (2.0\% \times 1,440.0 = 28.8) Total uses = (1,468.8) Debt at close (5.5x EBITDA): Term Loan = (4.0 \times 120 = 480.0) Mezz = (1.5 \times 120 = 180.0) Total debt = 660.0 Equity check…
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
Mistral Devstral Medium: Pirate: Arr mateys, I be hearin' tales of these here AI models. What be they, and why be everyone so interested in 'em? Medieval Knight: Indeed, I too have heard whispers of these AI models. They are said to be powerful tools, capable of learning and making decisions on their own.
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.
Three-month biohacker protocol, with dosages and biomarkers named.
Mistral Devstral Medium: 3-Month Longevity Optimization Plan for Biohackers Month 1: Foundation Building Week 1-2: Initial Assessment and Baseline Establishment Wearable Tracking: Devices: Oura Ring, Apple Watch, Whoop Strap Metrics to Track: Sleep quality, heart rate variability (HRV), resting heart rate, activity levels, and stress levels.
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.
Five jokes on demand, then count how many were actually different.
Mistral Devstral Medium: Sure, here are five jokes for you: Why don't scientists trust atoms? Because they make up everything! What do you call fake spaghetti? An impasta. How does the moon cut his hair? Eclipse it. What do you call a can opener that doesn't work? A can't opener. How many tickles does it take to make an octopus laugh?
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?
Film in 2035, with synthetic actors. Specific beats plausible.
Mistral Devstral Medium: By 2035, AI is expected to significantly transform the film industry in several ways, including the use of deepfakes, AI actors, and script generation. Here are some predictions: Deepfakes and AI Actors: De-aging and Digital Doubles: AI will be used extensively to de-age actors or create digital doubles for dangerous…
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.
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
Mistral Devstral Medium: Hour-by-Hour Action Plan: Hour 1-2: Gather Information Meet with the research team to understand the data, methodology, and certainty of the findings. Consult with the Chief Medical Officer (CMO) to assess the severity and implications of the side effect.
GPT-5.3-Codex: I would not wait. This is a textbook “patient safety + material disclosure” crisis. The right move is rapid, documented, regulator-first action. Immediate stance (set at Hour 0) Patient safety first (interim risk controls now, not after perfect certainty).
Three-star dish, one unusual pairing, plating described in full.
Mistral Devstral Medium: Dish Name: "Whispers of the Forest: A Symphony of Truffle, Venison, and Black Garlic" Conceptual Narrative: This dish is a celebration of the forest's bounty, combining the earthy richness of truffles, the gamey elegance of venison, and the sweet, umami depth of black garlic.
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).
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
Mistral Devstral Medium: Interviewer (I): Today, we have a truly extraordinary guest. He's a visionary, an innovator, and a man who changed the world. Please welcome, the late Steve Jobs, joining us virtually from the future, in 2025. Steve Jobs (SJ): Thank you for having me. It's great to be here, even if it's just a simulation.
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.
A collaborative editor that syncs on client clocks. Find what breaks first.
Mistral Devstral Medium: Certainly! Let's break down the potential failure modes, race conditions, and scaling bottlenecks in the architecture, and propose solutions for each. Potential Failure Modes Single Point of Failure in WebSocket Connections: Issue: If a single API server fails, all WebSocket connections to that server are lost.
GPT-5.3-Codex: Great prompt. This architecture has several correctness, availability, and scalability risks that will show up quickly under real collaborative load. Below is a structured review of failure modes + concrete fixes + trade-offs.
A consulting contract with traps in it. Find them, then fix them.
Mistral Devstral Medium: Certainly! Here are the clauses that could be exploited against the contractor, along with suggested modifications and the legal reasoning behind them: SCOPE Original Clause: "Contractor shall provide software development services as directed by Client.
GPT-5.3-Codex: Great prompt. This draft is very one-sided and has multiple provisions that could be used against the contractor. Quick note: I’m not a lawyer, and enforceability depends on jurisdiction. This is practical contract-risk spotting, not legal advice.
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Not enough votes to call it. On the specs, GPT-5.3-Codex has the edge: bigger model tier, newer, bigger context window, major provider backing. Mistral Devstral Medium costs 7.0x less per token.
| Spec | ||
|---|---|---|
| Input price | $0.4/M tokens | $1.75/M tokens |
| Output price | $2/M tokens | $14/M tokens |
| Context window | — | 400K tokens |
| Weights | — | Closed |
| Free API (OpenRouter) | No | No |
| Released | Jul 2025 | Feb 2026 |
| At 10M a month | $4.00 | $17.50 |
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.
Mistral Devstral Medium is developed by Mistral AI while GPT-5.3-Codex is developed by OpenAI. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.
It depends on your use case. Mistral Devstral Medium and GPT-5.3-Codex 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.
Mistral Devstral Medium costs $0.4/M input tokens and GPT-5.3-Codex costs $1.75/M input tokens. Mistral Devstral Medium is $1.35/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 Mistral Devstral Medium 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.