ChatGPT vs Gemini for writing

Every limit is published. Paid plans also have a monthly fair-use limit on AI cost: Pro $7.50, Max $20, Ultra $42, Studio $85. Using every message on your plan at typical sizes stays under it; very large messages and heavy research use it faster. Every limit, explained.

Writing: GPT-6 Luna passed 5 of 5 and Gemini 3.1 Pro (preview) 4 of 5. GPT-6 Luna answered 3.8× sooner at the median, 2.4 s against 9.1 s. GPT-6 Luna cost 92.3× less, $0.0005 against $0.0459 for the 5 replies. Gemini 3.1 Pro (preview)'s replies ran 23% longer, in tokens of reply, thinking not counted.

1. 1. Announce a second bakery shop on LinkedIn

   Everyday. GPT: 3 of 3 models passed, GPT-6 Luna the cheapest at $0.0001 · Gemini: 2 of 2 models passed, Gemini 3.8 Flash the cheapest at $0.0009. The prompt in full.

   GPT-6 Luna and Gemini 3.1 Pro both passed this one. GPT-6 Luna answered sooner (2.9 s to 9.5 s), and GPT-6 Luna's reply cost less ($0.0001 to $0.0113); GPT-6 Luna wrote 149 tokens of reply, Gemini 3.1 Pro 169.

   • GPT-6 Luna

     Passed: Graded 4.5 of 5 on average (lowest 4).

     We’re delighted to share that Crumb & Co. is opening a second shop in Leeds on 14 November!
     
     What began as one small bakery has grown thanks to the lovely people who’ve stopped by, shared a loaf, and made us feel part of the community. We’re excited to bring our freshly baked bread, pastries, and warm welcomes to a new neighbourhood.
     
     To celebrate opening day, we’ll be giving away free coffee. Pop in, say hello, and enjoy a cup with us—we’d love to meet you.
     
     Thank you to everyone who has supported Crumb & Co. so far. We can’t wait to open the doors and start this next chapter together. See you in Leeds on 14 November!

     389 tokens in, 149 out · 2.9 s · $0.0001 · 1 message on Pro · answered by openai/gpt-6-luna via OpenAI · September 27, 2026

   • Gemini 3.1 Pro

     Passed: Graded 4.0 of 5 on average (lowest 3).

     We are absolutely thrilled to share some wonderful news with you all. Our little bakery, Crumb & Co., is growing! Thanks to your incredible support over the years, we are opening the doors to our second shop in Leeds on the 14th of November. 
     
     When we first started baking, we never imagined we would be able to share our pastries and breads with so many lovely people. This new chapter in Leeds means the world to us, and we cannot wait to become a part of the local community. 
     
     To celebrate this exciting milestone, we would love for you to join us on our opening day. Pop in to say hello, check out the new space, and enjoy a free cup of coffee on us. We are so grateful for your continued support and look forward to welcoming you to our new home very soon.

     417 tokens in, 876 out (707 of them reasoning) · 9.5 s · $0.0113 · 1 message on Pro · answered by google/gemini-3.1-pro-preview via Google · September 27, 2026

2. 2. Rewrite corporate jargon in plain words

   Everyday. GPT: 2 of 3 models passed, GPT-6 Luna the cheapest at $0.0001 · Gemini: 1 of 2 models passed, Gemini 3.1 Pro at $0.0101. The prompt in full.

   GPT-6 Luna and Gemini 3.1 Pro both passed this one. GPT-6 Luna answered sooner (2.4 s to 8.8 s), and GPT-6 Luna's reply cost less ($0.0001 to $0.0101); GPT-6 Luna wrote 65 tokens of reply, Gemini 3.1 Pro 76.

   • GPT-6 Luna

     Passed: Graded 4.7 of 5 on average (lowest 4).

     In Q3, teams across the company worked together to focus more on customers. Retention measures improved by 12%, and the rate of customer loss fell by 0.3 percentage points in the enterprise segment. The company also adjusted its customer contact channels to make better use of available capacity.

     417 tokens in, 124 out (59 of them reasoning) · 2.4 s · $0.0001 · 1 message on Pro · answered by openai/gpt-6-luna via OpenAI · September 27, 2026

   • Gemini 3.1 Pro

     Passed: Graded 4.0 of 5 on average (lowest 3).

     In Q3, our teams worked together to adopt a more customer-focused approach. For our business clients, this resulted in a 12% increase in customer retention and a 0.30% (30 basis points) decrease in the rate of customers leaving. Additionally, we adjusted our various customer communication channels to make more efficient use of our time and resources.

     447 tokens in, 763 out (687 of them reasoning) · 8.8 s · $0.0101 · 1 message on Pro · answered by google/gemini-3.1-pro-preview via Google · September 27, 2026

3. 3. Decline a meeting and offer two times

   Everyday. GPT: 3 of 3 models passed, GPT-6 Luna the cheapest at $0.0001 · Gemini: 2 of 2 models passed, Gemini 3.8 Flash the cheapest at $0.0008. The prompt in full.

   GPT-6 Luna and Gemini 3.1 Pro both passed this one. GPT-6 Luna answered sooner (1.3 s to 6.2 s), and GPT-6 Luna's reply cost less ($0.0001 to $0.0058); GPT-6 Luna wrote 64 tokens of reply, Gemini 3.1 Pro 105.

   • GPT-6 Luna

     Passed: Graded 5.0 of 5 on average (lowest 5).

     Subject: Vendor Demo
     
     Hi Tom,
     
     Thanks for the invitation. I’m presenting to the board on Wednesday at 11:00, so I can’t make the demo then. Would Thursday at 10:00 or Friday at 14:00 work instead?
     
     Best,  
     [Your Name]

     395 tokens in, 64 out · 1.3 s · $0.0001 · 1 message on Pro · answered by openai/gpt-6-luna via OpenAI · September 27, 2026

   • Gemini 3.1 Pro

     Passed: Graded 5.0 of 5 on average (lowest 5).

     Subject: Re: Vendor Demo
     
     Hi Tom,
     
     Thank you for the invitation to the vendor demo on Wednesday at 11:00. Unfortunately, I won't be able to make it because I am presenting to the board at that time. 
     
     Could we reschedule for later in the week? I am available on Thursday at 10:00 or Friday at 14:00. Let me know if either of those times works for you.
     
     Best,
     
     [Your Name]

     428 tokens in, 415 out (310 of them reasoning) · 6.2 s · $0.0058 · 1 message on Pro · answered by google/gemini-3.1-pro-preview via Google · September 27, 2026

4. 4. A product announcement with five rules

   Hard. GPT: 3 of 3 models passed, GPT-6 Luna the cheapest at $0.0001 · Gemini: 1 of 2 models passed, Gemini 3.1 Pro at $0.0095. The prompt in full.

   GPT-6 Luna and Gemini 3.1 Pro both passed this one. GPT-6 Luna answered sooner (1.5 s to 9.2 s), and GPT-6 Luna's reply cost less ($0.0001 to $0.0095); GPT-6 Luna wrote 73 tokens of reply, Gemini 3.1 Pro 106.

   • GPT-6 Luna

     Passed: Graded 4.0 of 5 on average (lowest 3).

     Meet the Nordvik 2, a desk lamp designed to bring flexible light to your workspace. Choose from five brightness levels, charge it via USB-C, and turn its arm up to 270 degrees to direct light where you need it. The Nordvik 2 costs €79 and ships on 1 December. Ready to brighten your desk?

     406 tokens in, 73 out · 1.5 s · $0.0001 · 1 message on Pro · answered by openai/gpt-6-luna via OpenAI · September 27, 2026

   • Gemini 3.1 Pro

     Passed: Graded 4.0 of 5 on average (lowest 3).

     Introducing the Nordvik 2 desk lamp, designed to illuminate your workspace with precision. This new model features a highly flexible arm that turns 270 degrees, putting light exactly where you need it. You can easily tailor the brightness to suit any task, as it dims in five steps. Built for modern convenience, it also charges from USB-C to keep your setup clean and wire-free. The Nordvik 2 costs €79 and ships on 1 December. Are you ready to upgrade your daily lighting?

     435 tokens in, 715 out (609 of them reasoning) · 9.2 s · $0.0095 · 1 message on Pro · answered by google/gemini-3.1-pro-preview via Google · September 27, 2026

5. 5. Argue both sides of free buses

   Hard. GPT: 3 of 3 models passed, GPT-6 Luna the cheapest at $0.0001 · Gemini: 1 of 2 models passed, Gemini 3.8 Flash at $0.0011. The prompt in full.

   GPT-6 Luna passed this one and Gemini 3.1 Pro didn't. GPT-6 Luna answered sooner (2.5 s to 9.1 s), and GPT-6 Luna's reply cost less ($0.0001 to $0.0092); GPT-6 Luna wrote 186 tokens of reply, Gemini 3.1 Pro 207.

   • GPT-6 Luna

     Passed: Graded 4.3 of 5 on average (lowest 4).

     Making buses free would give every resident reliable access to jobs, school, health care, and daily necessities, regardless of income. It would also speed boarding, reduce fare-enforcement costs, and encourage people to leave cars at home—easing congestion, pollution, and parking pressure. A city that treats public transit as essential infrastructure, rather than a service people must qualify to afford, can build a more connected and equitable community.
     
     But “free” buses still have to be paid for, and the bill could divert money from more urgent improvements: frequent service, safer stops, cleaner vehicles, and routes to underserved neighborhoods. If buses remain slow, crowded, or unreliable, removing fares may do little to persuade drivers to switch, while reducing funds that could make transit genuinely useful. Targeted fare assistance can protect riders who need it most without subsidizing every trip, including those by people who can readily afford to pay.

     384 tokens in, 186 out · 2.5 s · $0.0001 · 1 message on Pro · answered by openai/gpt-6-luna via OpenAI · September 27, 2026

   • Gemini 3.1 Pro

     Failed: Graded 3.7 of 5 on average (lowest 3).

     Making city buses free is a powerful catalyst for economic equality and environmental sustainability. By eliminating fares, cities immediately remove a significant financial burden from low-income residents, improving their access to jobs, education, and healthcare. Furthermore, free transit incentivizes people to leave their cars at home, dramatically reducing traffic congestion and cutting harmful greenhouse gas emissions. This shift not only improves urban air quality but also reduces the long-term wear and tear on city infrastructure, ultimately creating a cleaner, fairer, and more accessible environment for all residents.
     
     However, eliminating fares fundamentally undermines the financial stability and quality of the transit system itself. Fares provide crucial revenue required for essential maintenance, route expansion, and driver salaries. Without this income, cities are forced to either slash service frequencies and coverage or drastically raise local taxes to cover the deficit. Consequently, free transit often results in overcrowded, unreliable, and dilapidated buses. Passengers ultimately prioritize speed, safety, and reliability over zero cost; a free bus is useless to a commuter if it never arrives on time.

     409 tokens in, 699 out (492 of them reasoning) · 9.1 s · $0.0092 · 1 message on Pro · answered by google/gemini-3.1-pro-preview via Google · September 27, 2026

• GPT-6 Astra vs Gemini 3.1 Pro: GPT-6 Astra 5 of 5, Gemini 3.1 Pro 4; GPT-6 Astra answered 1.9× sooner at the median and Gemini 3.1 Pro cost 1.2× less.

• GPT-6 Astra vs Gemini 3.8 Flash: GPT-6 Astra 5 of 5, Gemini 3.8 Flash 3; Gemini 3.8 Flash answered 1.2× sooner at the median and cost 8.4× less.

• GPT-6 Sol vs Gemini 3.1 Pro: 4 of 5 each; GPT-6 Sol answered 2.6× sooner at the median and cost 4.1× less. GPT-6 Sol vs Gemini 3.1 Pro (preview), on every job.

• GPT-6 Sol vs Gemini 3.8 Flash: GPT-6 Sol 4 of 5, Gemini 3.8 Flash 3; GPT-6 Sol answered 1.1× sooner at the median and Gemini 3.8 Flash cost 1.7× less. GPT-6 Sol vs Gemini 3.8 Flash, on every job.

• GPT-6 Luna vs Gemini 3.1 Pro: GPT-6 Luna 5 of 5, Gemini 3.1 Pro 4; GPT-6 Luna answered 3.8× sooner at the median and cost 92.3× less.

• GPT-6 Luna vs Gemini 3.8 Flash: GPT-6 Luna 5 of 5, Gemini 3.8 Flash 3; GPT-6 Luna answered 1.6× sooner at the median and cost 13.3× less. GPT-6 Luna vs Gemini 3.8 Flash, on every job.

Every GPT and Gemini reply above was checked the same way as every other model's, by the rules published with the prompts: how the writing prompts are scored, and each one in full.

• The lineups

  GPT: 3 models, GPT-6 Astra, GPT-6 Sol, and GPT-6 Luna. Gemini: 2 models, Gemini 3.1 Pro (preview) and Gemini 3.8 Flash.

• Price per message

  The least expensive GPT model is GPT-6 Luna (60 messages a day on Pro); the least expensive Gemini model is Gemini 3.8 Flash (250 messages a month on Pro).

• Context window

  GPT goes up to 1.05M tokens (GPT-6 Astra); Gemini up to 1.05M tokens (Gemini 3.1 Pro (preview)).

• Images and PDFs

  Every model here reads images. Every model here takes a PDF as a whole file.

• On the Free plan

  Free's one-time trial of 5 messages covers GPT-6 Sol, GPT-6 Luna, Gemini 3.1 Pro (preview), and Gemini 3.8 Flash. Paid plans have every model, with messages every month.

In llmwise, a message to GPT or Gemini goes to the model's maker, or through OpenRouter when llmwise can't reach the maker directly. The Privacy Policy has the details.