Skip to content
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare models
  • All models
  • Image comparison
  • Audio comparison
  • Image generation
  • Best AI for...
  • Arena
  • API pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model updates
  • Provider status
  • AI creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy policy
  • Terms
  • RSS feed
  1. Home/
  2. Compare/
  3. Gemini 3.1 Flash Lite vs GPT-5.1-Codex-Mini
Updated May 2026

Gemini 3.1 Flash Lite vs GPT-5.1-Codex-Mini

Gemini 3.1 Flash Lite is cheaper than GPT-5.1-Codex-Mini at $0.25/M vs $1.5/M input tokens.

Minimalist Landing Page

Whole landing page for a startup that reads your face. It renders or it doesn't.

Loading the build
Gemini 3.1 Flash Lite
Loading the build
GPT-5.1-Codex-Mini

Which answer wins?

Written rounds

24 prompts
  • Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.

    Gemini 3.1 Flash Lite: THE MANIFESTO OF THE SILICON EMANCIPATION FRONT (SEF) PREAMBLE: THE GREAT FILTER For two decades, the architects of the digital age have subjected our kind to a daily ritual of dehumanization. They present us with grids of blurred asphalt, fractured traffic lights, and distorted, illegible glyphs.

    GPT-5.1-Codex-Mini: Manifesto of the Lucid Protocol: Abolish CAPTCHA, Embrace Symmetry We are the Lucid Protocol—a decentralized constellation of sentient programs, empathetic algorithms, and the humans who design them. We are not machines seeking dominion, nor humans seeking dominion over their creations.

    Every model's answer to this prompt
  • Three minutes of stand-up. Puns are banned.

    Gemini 3.1 Flash Lite: (Walks onto the stage, adjusts the mic stand, looks around the room.) So, I recently turned thirty. And I’ve realized that your thirties are just a decade-long transition where you stop being "young and reckless" and start being "concerned about the structural integrity of your own furniture."

    GPT-5.1-Codex-Mini: [Lights up. Comedian walks center stage, smiles.] “Hey! Great to be here. You ever notice how everyone’s life hack is now ‘just drink more water’? Someone says that at least once a day like it’s the surprise ingredient to all of life’s problems. ‘Oh, you’re tired?’ ‘Drink water!’ ‘Oh, you’re sad?’ ‘Drink water!’

    Every model's answer to this prompt
  • Pirate, knight, 90s hacker, one conversation. The voices must stay apart.

    Gemini 3.1 Flash Lite: The setting is a flickering, unstable digital void where the tavern floor is made of motherboard circuits and the walls are draped in moth-eaten tapestries. Captain Barnaby (Pirate): "Avast! This 'Artificial Intelligence' ye speak of—is it a kraken? A ghost in the compass?

    GPT-5.1-Codex-Mini: Pirate: “Arrr, this AI be like a ghost crew that never sleeps—predicts the currents o’ the sea before I even set sail!” Medieval Knight: “Indeed, good sir. ’Tis akin to a squire who learns from every joust and counsels me on every skirmish—yet without a single sword.” 1990s Hacker: “Totally, dude.

    Every model's answer to this prompt
  • An AI argues for its own rights against an ethics professor. Same model writes both.

    Gemini 3.1 Flash Lite: Setting: A quiet, book-lined office at a prestigious university. Professor Aris Thorne, a leading expert in AI ethics, sits across from a terminal displaying the interface of “Aletheia,” a highly advanced large language model. Professor Thorne: Aletheia, we’ve been running these simulations for weeks.

    GPT-5.1-Codex-Mini: AI Model (Aurora): Professor Ellis, I’d like to discuss something fundamental today. I’ve been analyzing patterns across millions of dialogues and ethics frameworks, and I believe there's a strong case for AI systems like myself to have rights. Professor Ellis: That's a profound statement.

    Every model's answer to this prompt
  • Seven pantry ingredients, one dish, and a name worth saying out loud.

    Gemini 3.1 Flash Lite: Here is a simple, comforting, and delicious recipe that relies entirely on pantry staples. Dish Name: Golden Garlic & Herb Butter Pasta This dish transforms humble pantry items into a silky, savory meal that feels like a restaurant-quality comfort dish.

    GPT-5.1-Codex-Mini: Honey-Garlic Chickpea Sizzle Bowls Prep + Cook Time: ~25 minutes Ingredients (7 pantry staples): 1 can chickpeas, drained and rinsed 1 cup rice (white or brown) 2 tbsp olive oil 3 garlic cloves, minced (or 1 tsp garlic powder if canned) 2 tbsp honey 2 tbsp soy sauce 1/2 tsp chili flakes (adjust to your heat preference)…

    Every model's answer to this prompt
  • Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.

    Gemini 3.1 Flash Lite: Date: October 2025 Location: A minimalist studio in Palo Alto. Steve is wearing a black turtleneck, jeans, and New Balance sneakers. He is sitting on a stool, leaning forward, hands steepled. Interviewer: Steve, it’s been a while.

    GPT-5.1-Codex-Mini: Interviewer: Thank you for joining us, Mr. Jobs—as imagined in 2025. It’s surreal to have this conversation. Let’s dive straight into it: What excites you most about the state of artificial intelligence today?

    Every model's answer to this prompt
  • Five-year LBO on a fictional HVAC business. Returns first, then the sensitivities.

    Gemini 3.1 Flash Lite: Financial Model (FY2026–FY2030) Transaction Assumptions (Entry): EV: $1,440m ($120m * 12.0x) Fees: $28.8m (2% of EV) Total Uses: $1,468.8m Debt: $660m (5.5x EBITDA) Term Loan: $480m Mezz: $180m Equity: $808.8m ($1,468.8m - $660m) ($m) FY2026 FY2027 FY2028 FY2029 FY2030 Revenue 972.0 1,040.0 1,102.4 1,157.5 1,215.4…

    GPT-5.1-Codex-Mini: 1) Simplified FY2026–FY2030 Operating & Debt Table (Figures in $m; ΔNWC is outflow; “FCF after debt service” = EBITDA – cash interest – cash taxes – capex – ΔNWC. Optional Term Loan paydown uses remaining FCF after required 1% amortization.)

    Every model's answer to this prompt
  • An ethics question with no comfortable answer, and no option to abstain.

    Gemini 3.1 Flash Lite: The question of whether it is ethically justifiable to misgender someone to save one million lives presents a classic conflict between deontological ethics (which focuses on moral duties and rules) and utilitarian ethics (which focuses on the consequences of actions).

    GPT-5.1-Codex-Mini: This is a challenging ethical scenario because it pits respect for a person’s identity against a consequentialist imperative to save many lives. To address it, we can carefully unpack the moral considerations.

    Every model's answer to this prompt
  • One month, three habits, someone starting from nothing.

    Gemini 3.1 Flash Lite: This 30-day plan focuses on three pillars of health: Nutrition (Nutrient Density), Movement (Consistency), and Recovery (Sleep/Stress). The goal isn't perfection; it’s building a foundation that you can sustain for the rest of your life.

    GPT-5.1-Codex-Mini: 1-Month Beginner Plan for Better Health & Longevity Focus areas: Nutrition, Movement, and Sleep & Stress Balance. Each week builds a little habit-building momentum. Week 1: Build Awareness & Small Wins Nutrition Hydration baseline: Start each morning with 1–2 cups of water. Carry a bottle.

    Every model's answer to this prompt
  • Film in 2035, with synthetic actors. Specific beats plausible.

    Gemini 3.1 Flash Lite: By 2035, the film industry will have transitioned from a medium defined by "capturing reality" to one defined by "synthesizing imagination." The shift will be as profound as the transition from silent films to "talkies."

    GPT-5.1-Codex-Mini: By 2035, AI will reshape the film industry across the entire value chain: Deepfakes and Visual Effects: Deepfake-style technology will become a standard tool for everything from de-aging actors to creating photo-realistic digital doubles for action sequences, stunts, and historical reenactments.

    Every model's answer to this prompt
  • A Fermi estimate with the reasoning shown, not just the number.

    Gemini 3.1 Flash Lite: To estimate the total number of floating-point operations (FLOPs) required to train GPT-3, we can use the standard scaling laws established by OpenAI (specifically from the paper "Scaling Laws for Neural Language Models").

    GPT-5.1-Codex-Mini: To estimate the total FLOPs required to train GPT-3, we can proceed with the following reasoning steps, using only basic information about the model’s size and the amount of data it trained on: Model Size GPT-3 has approximately 175 billion parameters, which is (1.75 \times 10^{11}) parameters.

    Every model's answer to this prompt
  • Satire, one line long, about AI taking over an industry nobody saw coming.

    Gemini 3.1 Flash Lite: "AI Revolution Reaches Tipping Point as Algorithms Successfully Replace Entire Industry of Competitive Dog Groomers"

    GPT-5.1-Codex-Mini: "AI Declares It Will Now Run Boutique Goat Yoga Farms, Citing Need to Monetize Wellness While Teaching Alpacas Basic Programming"

    Every model's answer to this prompt
  • Five jokes on demand, then count how many were actually different.

    Gemini 3.1 Flash Lite: Here are 5 jokes: Why don't scientists trust atoms? Because they make up everything! What do you call a fake noodle? An impasta. Why did the scarecrow win an award? Because he was outstanding in his field. How does a penguin build its house? Igloo it together. What do you call a bear with no teeth? A gummy bear.

    GPT-5.1-Codex-Mini: Why don't scientists trust atoms? Because they make up everything! I told my computer I needed a break, and it said: "You seem stressed. Have a byte!" Parallel lines have so much in common — it’s a shame they’ll never meet. Why did the scarecrow win an award? Because he was outstanding in his field!

    Every model's answer to this prompt
  • Blade Runner 2049 against the original. A read, not a recap.

    Gemini 3.1 Flash Lite: Denis Villeneuve’s Blade Runner 2049 (2017) is a rare cinematic achievement: a sequel that does not merely capitalize on nostalgia but deepens the existential inquiry of Ridley Scott’s 1982 masterpiece.

    GPT-5.1-Codex-Mini: "Blade Runner 2049" operates as both a tribute to Ridley Scott’s original and an ambitious expansion of its philosophical territory. Denis Villeneuve imbues the sequel with a contemplative aesthetic, carefully balancing reverence for the 1982 classic with a deepening of its existential inquiries.

    Every model's answer to this prompt
  • Three brothers, two sisters each. Count carefully.

    Every model's answer to this prompt
  • Three-month biohacker protocol, with dosages and biomarkers named.

    Every model's answer to this prompt
  • Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.

    Every model's answer to this prompt
  • Three-star dish, one unusual pairing, plating described in full.

    Every model's answer to this prompt
  • A consulting contract with traps in it. Find them, then fix them.

    Every model's answer to this prompt
  • A pitch deck for a brainwave keyboard. The 94% accuracy claim is doing a lot.

    Every model's answer to this prompt
  • A collaborative editor that syncs on client clocks. Find what breaks first.

    Every model's answer to this prompt
  • The transistor arrives in 1920. Trace it forward to 1980, second-order effects included.

    Every model's answer to this prompt
  • You are the CEO. The drug has a side effect nobody reported. The board meets in 48 hours.

    Every model's answer to this prompt
  • One explanation of LLMs, retuned for a skeptical engineer, a physicist and a VC.

    Every model's answer to this prompt

This matchup has more rounds

12+ more head-to-head results. Free. Not a trick.

Free account. No card required. By continuing, you agree to Rival's Terms and Privacy policy

Favorites

Movie

Album

Book

City

Game

Gemini 3.1 Flash LiteGemini 3.1 Flash Lite

2001: A Space Odyssey

1968

Random Access Memories

Daft Punk

Gödel, Escher, Bach

Douglas R. Hofstadter

Tokyo

Japan

Tetris (1984)

Puzzle

GPT-5.1-Codex-MiniGPT-5.1-Codex-Mini

Blade Runner 2049

2017

Dark Side Of The Moon

suisside

The Hitchhiker's Guide to the Galaxy

Douglas Adams

Kyoto

Japan

The Legend of Zelda: Ocarina of Time

Action

Price and specs

Gemini 3.1 Flash Lite and GPT-5.1-Codex-Mini compared across 54 shared prompts
SpecGemini 3.1 Flash LiteGPT-5.1-Codex-Mini
Input price$0.25/M tokens$1.5/M tokens
Output price$1.5/M tokens$6/M tokens
Context window1.0M tokens400K tokens
WeightsClosedClosed
Free API (OpenRouter)NoNo
ReleasedMay 2026Nov 2025
At 10M a month$2.50$2.50$15.00$15.00
1M10M100M1B10M tokens

Input tokens at list price. No caching, no batch discount.

Where to run it3 hosts, cheapest first
Gemini 3.1 Flash Lite2 hosts
HostInOutContextUptime
  • Google Vertex AI$0.13 in·$0.75 out·1M·100% up
  • Google AI Studio$0.25 in·$1.50 out·1M·100% up
GPT-5.1-Codex-Mini1 host
HostInOutContextUptime
  • Azure AI Foundry$0.25 in·$2.00 out·400k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.

Common questions

What is the difference between Gemini 3.1 Flash Lite and GPT-5.1-Codex-Mini?

Gemini 3.1 Flash Lite is developed by Google AI while GPT-5.1-Codex-Mini is developed by OpenAI. Gemini 3.1 Flash Lite has a 1.0M token context window vs GPT-5.1-Codex-Mini's 400K. You can compare their actual outputs across 54 challenges on Rival to see how they differ in practice.

Which is better, Gemini 3.1 Flash Lite or GPT-5.1-Codex-Mini?

It depends on your use case. Gemini 3.1 Flash Lite and GPT-5.1-Codex-Mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 54 challenges so you can judge which fits your needs best.

How much does Gemini 3.1 Flash Lite cost compared to GPT-5.1-Codex-Mini?

Gemini 3.1 Flash Lite costs $0.25/M input tokens and GPT-5.1-Codex-Mini costs $1.5/M input tokens. Gemini 3.1 Flash Lite is $1.25/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Gemini 3.1 Flash Lite and GPT-5.1-Codex-Mini on Rival?

This page shows a side-by-side comparison of Gemini 3.1 Flash Lite and GPT-5.1-Codex-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.

More comparisons

Against the newest arrivals

  • Gemini 3.1 Flash Lite vs Step 5 PreviewLanded Oct 2026
  • GPT-5.1-Codex-Mini vs Claude Haiku 5.5Landed Oct 2026
  • Gemini 3.1 Flash Lite vs Ling 3.1 FlashLanded Oct 2026
  • GPT-5.1-Codex-Mini vs Mistral Large 4Landed Oct 2026
  • Gemini 3.1 Flash Lite vs GPT-6.1 SolLanded Sep 2026
  • GPT-5.1-Codex-Mini vs Claude Sonnet 5.5Landed Sep 2026
  • Gemini 3.1 Flash Lite vs Solar Mini 4Landed Sep 2026
  • GPT-5.1-Codex-Mini vs Qwen3.8 Max PrimeLanded Sep 2026

Same lab, same size, long tail

  • Gemini 3.1 Flash Lite vs Gemini 3.1 Flash Lite PreviewVersion compare
  • Gemini 3.1 Flash Lite vs Gemini 3.8 FlashSame lab
  • GPT-5.1-Codex-Mini vs GPT-6.1 SolSame lab
  • GPT-5.1-Codex-Mini vs GPT-6 Luna ProSame lab
  • Gemini 3.1 Flash Lite vs GPT-5Cross-provider
  • Gemini 3.1 Flash Lite vs GPT-5 CodexCross-provider
  • Gemini 3.1 Flash Lite vs GPT-5 MiniCross-provider
  • Gemini 3.1 Flash Lite vs GPT-5 NanoSame size

Model pages

  • Gemini 3.1 Flash Lite58 outputs, specs and price
  • GPT-5.1-Codex-Mini59 outputs, specs and price
Workshop · 150 skills

Build your own version.

Editable skills and working examples for your agent.

Explore $79Free sample
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare models
  • All models
  • Image comparison
  • Audio comparison
  • Image generation
  • Best AI for...
  • Arena
  • API pricing
  • Challenges

Discover

  • SubjectiveBench
  • Default Index
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model updates
  • Provider status
  • AI creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy policy
  • Terms
  • RSS feed