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TokenMath.net
Updated 2026-09-22 11:16 UTC
Head-to-Head Specification Battle

OpenAI o3 vs Gemini 2.5 Flash-Lite

Side-by-side technical and economic comparison between OpenAI's OpenAI o3 and Google's Gemini 2.5 Flash-Lite.

Core Technical & Pricing Comparison
MetricOpenAI o3Gemini 2.5 Flash-LiteAdvantage
Provider OrganizationOpenAIGoogle
Standard Input / 1M$2.00$0.10Gemini 2.5 Flash-Lite (95% lower)
Cached Input / 1M$0.50$0.01Gemini 2.5 Flash-Lite lower
Output / 1M$8.00$0.40Gemini 2.5 Flash-Lite lower
Context Window200k1.05MGemini 2.5 Flash-Lite (1.05M)
Max Generation Tokens100k8.2kOpenAI o3
Tokenizer FamilyOpenAI o200k_base (200k vocabulary)Google Gemini SentencePiece (256k vocabulary)

Interactive Side-by-Side Cost Simulator

Live Delta
Input Tokens / Req2,500
Output Tokens / Req800
Daily Requests10,000
OpenAI o3
$2,857.50 / month
$0.00953 / request
Gemini 2.5 Flash-LiteLOWER COST
$137.25 / month
$0.00046 / request
Selecting Gemini 2.5 Flash-Lite saves $2,720.25 / month (95.2% savings) over OpenAI o3.

When to Choose OpenAI o3

Opt for OpenAI o3 when your engineering requirements prioritize OpenAI's ecosystem, specific tokenizer efficiencies (Exact BPE (o200k_base)), or when your expected prompt-to-completion ratios favor its $2/M input rate.

When to Choose Gemini 2.5 Flash-Lite

Opt for Gemini 2.5 Flash-Lite when looking for Google's tooling integration, specific context window depth (1.05M tokens), or when output generation volume favors its $0.4/M rate.