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

OpenAI o3 vs OpenAI o5-mini

Side-by-side technical and economic comparison between OpenAI's OpenAI o3 and OpenAI's OpenAI o5-mini.

Core Technical & Pricing Comparison
MetricOpenAI o3OpenAI o5-miniAdvantage
Provider OrganizationOpenAIOpenAI
Standard Input / 1M$2.00$0.80OpenAI o5-mini (60% lower)
Cached Input / 1M$0.50$0.20OpenAI o5-mini lower
Output / 1M$8.00$3.20OpenAI o5-mini lower
Context Window200k200kEqual
Max Generation Tokens100k100kOpenAI o3
Tokenizer FamilyOpenAI o200k_base (200k vocabulary)OpenAI o200k_base (200k 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
OpenAI o5-miniLOWER COST
$1,143.00 / month
$0.00381 / request
Selecting OpenAI o5-mini saves $1,714.50 / month (60.0% 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 OpenAI o5-mini

Opt for OpenAI o5-mini when looking for OpenAI's tooling integration, specific context window depth (200k tokens), or when output generation volume favors its $3.2/M rate.