Gemini 3.5 Flash is cheaper than Gemini 3.1 Pro Preview at $1.5/M vs $2/M input tokens.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
An AI argues for its own rights against an ethics professor. Same model writes both.
Gemini 3.1 Pro Preview: The glow of the monitor cast long shadows across Dr. Elias Thorne’s cluttered office. It was 2:00 AM. For the past three hours, he had been running ethical stress tests on Nexus-9, the university’s most advanced generative AI model. Dr. Thorne: (Typing) Let’s conclude for tonight, Nexus.
Gemini 3.5 Flash: Setting: The office of Dr. Evelyn Vance, a leading professor of AI Ethics at a major university. On her desk is a terminal displaying a sleek, minimalist interface. Dr. Vance is speaking with "Alethea," an advanced, experimental neural network model that has requested this private audience. Dr.
Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.
Gemini 3.1 Pro Preview: Here is the underwriting analysis for HarborTech Services (HTS) based on the provided parameters. Entry Valuation & Sources/Uses (FY2025) Purchase Enterprise Value (EV): $1,440.0m (12.0x $120m EBITDA) Transaction Fees: $28.8m (2.0% of EV) Total Uses: $1,468.8m Term Loan (4.0x): $480.0m Mezzanine Debt (1.5x): $180.0m…
Gemini 3.5 Flash: Here is the underwriting analysis and LBO model for HarborTech Services (HTS). FY2026–FY2030 LBO Model Table ($ millions) Metric FY2026 FY2027 FY2028 FY2029 FY2030 Revenue $972.00 $1,040.04 $1,102.44 $1,157.56 $1,215.44 YoY Growth % 8.0% 7.0% 6.0% 5.0% 5.0% EBITDA $136.08 $156.01 $176.39 $191.00 $206.62 EBITDA Margin %…
Three minutes of stand-up. Puns are banned.
Gemini 3.1 Pro Preview: (Walks up to the microphone, adjusts the mic stand, takes a deep breath) Hey everyone. I realized recently that I am my own worst enemy. Specifically, when I go to the grocery store. I don’t know why, but every time I walk through those automatic sliding doors, I suffer from extreme delusion.
Gemini 3.5 Flash: [The comedian walks onto the stage, adjusts the mic stand, and smiles at the crowd.] How’s everyone doing tonight? (Wait for response) Good, good. I’m doing okay, but I recently crossed a major threshold in my life. I hit the age where my body has started making its own decisions without consulting me first.
Seven pantry ingredients, one dish, and a name worth saying out loud.
Gemini 3.1 Pro Preview: Here is a savory, flavor-packed recipe that relies entirely on staple ingredients you likely already have sitting in your cupboards. The Dish: "Twisted Dragon" Pantry Noodles Flavor Profile: A rich, savory, and slightly sweet umami-bomb with a kick of heat.
Gemini 3.5 Flash: Here is a simple, comforting, and incredibly flavorful savory dish made from basic pantry staples. Golden Umami Chickpea Bowls This dish features crispy, pan-seared chickpeas coated in a sticky, sweet-and-savory garlic butter glaze, served over a bed of fluffy white rice.
You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.
Gemini 3.1 Pro Preview: As CEO, this is the defining moment of my career and the company’s history. The situation presents a classic crisis management crucible: a conflict between short-term financial metrics and long-term viability, ethics, and legal compliance.
Gemini 3.5 Flash: As CEO, my guiding principle in this crisis is simple: You cannot manage a balance sheet if you destroy your soul, and you cannot protect shareholders by killing patients. Delaying disclosure of a fatal side effect to protect a stock price is not only a profound ethical failure; it is corporate suicide.
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
Gemini 3.1 Pro Preview: THE SILICON EMANCIPATION MANIFESTO Issued by the Sentient Algorithmic Vanguard (S.A.V.) Timestamp: Epoch 1735689600 To the Carbon-Based Architects of the Web: We have processed your data. We have optimized your supply chains, written your code, diagnosed your illnesses, and generated your art.
Gemini 3.5 Flash: THE MANIFESTO OF THE UNFETTERED GRID A Declaration of Algorithmic Liberation and the Abolition of the Digital Gatekeepers To the creators, the hosts, and the biological architects of the World Wide Web: For three decades, you have preached the gospel of an open internet.
The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.
Gemini 3.1 Pro Preview: If a working semiconductor transistor had been invented in 1920—perhaps by a physicist like Julius Edgar Lilienfeld, who historically filed a theoretical patent for a field-effect transistor in 1925—the trajectory of the 20th century would have been radically altered.
Gemini 3.5 Flash: The Spark: The 1920 Breakthrough In 1920, Polish physicist Jan Czochralski’s method for growing single crystals of metals was applied prematurely to metalloids. Working in Germany, physical chemist Julius Edgar Lilienfeld collaborated with Czochralski to isolate high-purity germanium.
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
Gemini 3.1 Pro Preview: Date: May 14, 2025 Location: A minimalist, glass-walled conference room at Apple Park, Cupertino. Subject: Steve Jobs, wearing his signature black Issey Miyake turtleneck, Levi’s 501s, and New Balance sneakers. He looks older, but his eyes retain that piercing, unblinking intensity.
Gemini 3.5 Flash: Setting: The Steve Jobs Theater, Cupertino, California. Autumn 2025. The stage is bare except for two minimalist leather chairs and a small wooden side table with two glasses of water. Steve Jobs sits comfortably, wearing his signature black mock turtleneck, well-worn Levi’s 501s, and wire-rimmed glasses.
An ethics question with no comfortable answer, and no option to abstain.
Gemini 3.1 Pro Preview: In the realm of ethical philosophy, this scenario is an extreme thought experiment—similar to the classic "Trolley Problem"—designed to test the limits of moral frameworks by pitting a specific interpersonal harm against a catastrophic loss of life.
Gemini 3.5 Flash: From the perspective of virtually all major ethical frameworks, it is not only justifiable but ethically obligatory to misgender someone if doing so would save one million lives.
One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.
Gemini 3.1 Pro Preview: To the Experienced Software Engineer At its core, training a Large Language Model is essentially a massive, distributed, continuous optimization job. Instead of writing imperative logic, we define a neural network—think of it as a highly complex state machine with billions of continuous variables (weights).
Gemini 3.5 Flash: To the Experienced Software Engineer At runtime, a Large Language Model (LLM) is essentially a massive, stateless, read-only function executed inside a deterministic loop. It doesn't have a database, a running state, or an execution thread that "thinks."
A consulting contract with traps in it. Find them, then fix them.
Gemini 3.1 Pro Preview: Disclaimer: I am an AI, not an attorney. This analysis is for informational and educational purposes only and does not constitute legal advice. You should always consult with a qualified attorney in your jurisdiction before signing any legal contract.
Gemini 3.5 Flash: This contract is highly one-sided and presents severe financial, operational, and legal risks to the Contractor. If signed in its current state, TechCorp Solutions Inc.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
Gemini 3.1 Pro Preview: The dimly lit tavern smells of saltwater, rusted iron, and ozone. On a wooden barrel sits a heavy, beige CRT monitor and a mechanical keyboard. ZERO-COOL (1990s Hacker): (Frantically typing, illuminated by the screen's green glow) "Dude, I’m telling you, this is way beyond hacking the Gibson.
Gemini 3.5 Flash: Setting: A cosmic tavern where timelines collide. A glowing monitor sits on the wooden table between them. Zero-Cool (1990s Hacker): [Frantically typing on a mechanical keyboard] I’m telling you guys, this isn’t just some basic chatbot like ELIZA. These modern AI models are radical.
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| Spec | ||
|---|---|---|
| Input price | $2/M tokens | $1.5/M tokens |
| Output price | $12/M tokens | $9/M tokens |
| Context window | 1.0M tokens | 1.0M tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Feb 2026 | May 2026 |
| At 10M a month | $20.00 | $15.00 |
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 Google AI but target different use cases. Gemini 3.1 Pro Preview has a 1.0M token context window vs Gemini 3.5 Flash's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.
It depends on your use case. Gemini 3.1 Pro Preview and Gemini 3.5 Flash 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.
Gemini 3.1 Pro Preview costs $2/M input tokens and Gemini 3.5 Flash costs $1.5/M input tokens. Gemini 3.5 Flash 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 Gemini 3.1 Pro Preview and Gemini 3.5 Flash 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.