Skip to main content
AI HQ

Type at least two characters. Try a model (“gpt-5 mini”), a provider (“anthropic”), or a topic (“coding”).

↑↓ navigate · open · esc closeLive data from OpenRouter

Comparison

Gemini vs GPT-5: Google's flagship against OpenAI's

Gemini's very long context and multimodal input against GPT-5's ecosystem and pricing.

Editorial updated 21 Sept 2026

Source: OpenRouter (live)

Google's Gemini line is the most aggressive on context length and multimodal input, and often on price. OpenAI's GPT-5 is the default in most developer tooling. If you are building on either company's wider platform (Workspace and Vertex on one side, the OpenAI ecosystem on the other) that integration usually decides it.

Where the choice is open, look at the context and modality rows. Gemini regularly declares a context window several times larger than GPT-5's, which changes how you architect retrieval: fewer chunks, more raw documents in the prompt. GPT-5 tends to be the stronger fit for tool-heavy agents and strict structured output.

Both prices below are live. Gemini's pricing frequently changes at version boundaries, so revisit this page rather than relying on a figure you saw last quarter.

Live figures

The numbers

Best value in each row is highlighted. “Not declared” means the provider does not advertise the feature on its listing.

Side-by-side comparison of Google: Gemini 3.1 Pro Preview, OpenAI: GPT-5.6 Luna Pro
Attribute
GoogleGemini 3.1 Pro Previewgoogle/gemini-3.1-pro-preview
OpenAIGPT-5.6 Luna Proopenai/gpt-5.6-luna-pro
Input priceUSD per 1M tokens$2.00$0.20 (best)
Output priceUSD per 1M tokens$12.00$1.20 (best)
Blended price75% in / 25% out$4.50$0.45 (best)
Vs. market median5.6× dearer44% cheaper
Value rankcheapest = 1#358#143 (best)
Context windowtokens1.0M1.1M (best)
Max outputtokens66K128K (best)
Input modalitiesaudio, file, image, text, videofile, image, text
Output modalitiestexttext
Tool callingDeclaredDeclared
ReasoningDeclaredDeclared
Structured outputDeclaredDeclared
Listed on OpenRouter2026-02-192026-07-09 (best)

Blended price assumes a 3:1 input-to-output token mix. Median is across all 417 priced models.

Add or swap models

Read-out

What the numbers say

  • OpenAI: GPT-5.6 Luna Pro is the cheapest here at $0.45/M blended — 10× less than Google: Gemini 3.1 Pro Preview.
  • OpenAI: GPT-5.6 Luna Pro offers the largest context window (1.1M tokens) versus 1.0M for Google: Gemini 3.1 Pro Preview.

Our view

Which should you choose?

Gemini 3.1 Pro Preview
Choose Gemini for very large contexts, native multimodal input and Google Cloud or Workspace integration.
GPT-5.6 Luna Pro
Choose GPT-5 for the deepest tooling and library support and the most predictable structured output.

Models

Model pages

Full pricing history, capabilities and alternatives for each model in this comparison.

  1. $4.50

    /M blended

  2. $0.450

    /M blended

More comparisons

Other head-to-heads

More →

Newsletter

Stay Ahead of AI

Get the most important developments in artificial intelligence delivered directly to your inbox.

No hype. No spam.

Just trusted insights, major model releases, pricing updates, benchmark changes, product reviews, and practical guidance from across the AI ecosystem.

  • Weekly AI Briefing
  • Major Model Releases
  • Pricing & Benchmark Updates
  • Unsubscribe Anytime

The AI HQ Briefing

One email a week. Read in five minutes.

By subscribing you agree to receive the AI HQ newsletter. Your address is processed by our email delivery provider and never sold. Unsubscribe anytime.