Gemini 2.5 Flash vs GPT-5 Mini

Google's Gemini 2.5 Flash against OpenAI's GPT-5 Mini — pricing, benchmarks, context, and best use cases compared side by side.

Last updated March 2026 · Compare other models
Quick Verdict

Gemini 2.5 Flash and GPT-5 Mini are virtually tied on benchmark quality (Elo 1315 vs 1310), but Gemini 2.5 Flash is 67% cheaper on blended cost. Gemini 2.5 Flash offers a larger context window (1M vs 400K).

Gemini 2.5 Flash
Google
GPT-5 Mini
OpenAI
Input Price $0.15/1M $0.25/1M
Output Price $0.60/1M $2.00/1M
Blended Price $0.38/1M $1.12/1M
LMSYS Elo 1315 1310
Context Window 1,000,000 400,000
Provider Google OpenAI

Pricing breakdown

When comparing LLM API pricing, Gemini 2.5 Flash charges $0.15 per 1M input tokens compared to GPT-5 Mini's $0.25 — a 40% difference. For output tokens, Gemini 2.5 Flash costs $0.60/1M versus $2.00/1M for GPT-5 Mini. On a blended basis (averaging input and output), Gemini 2.5 Flash comes in at $0.38/1M tokens versus $1.12/1M for GPT-5 Mini.

Quality & benchmarks

In terms of quality, Gemini 2.5 Flash (Elo 1315) and GPT-5 Mini (Elo 1310) are essentially neck-and-neck on the LMSYS Chatbot Arena leaderboard. The 5-point gap is within the margin of uncertainty, meaning both models deliver comparable output quality for most use cases. Your choice between them should come down to pricing, ecosystem preferences, and specific feature needs rather than raw benchmark performance.

Context window comparison

Gemini 2.5 Flash provides a significantly larger context window at 1M tokens compared to GPT-5 Mini's 400K tokens — 2.5x more capacity for processing long documents, large codebases, or extended conversations. With 1M tokens, Gemini 2.5 Flash can handle entire books, repositories, or multi-document analysis in a single prompt.

Monthly cost estimate

Adjust the sliders to see how costs compare for your workload.

Gemini 2.5 Flash
per month
GPT-5 Mini
per month

Choose Gemini 2.5 Flash if you need...

Ultra-cheap with 1M context
Best budget option from Google
Great for bulk processing

Choose GPT-5 Mini if you need...

Extremely affordable
400K context at budget pricing
Good quality for the price tier

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