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

OpenAI o1 vs DeepSeek-V4.1-Reasoner

Side-by-side technical and economic comparison between OpenAI's OpenAI o1 and DeepSeek's DeepSeek-V4.1-Reasoner.

Endpoint Availability & Transition Notice

OpenAI o1: Classified as a Legacy Reference model (Generally Available).

Core Technical & Pricing Comparison
MetricOpenAI o1DeepSeek-V4.1-ReasonerAdvantage
Provider OrganizationOpenAIDeepSeek
Standard Input / 1M$15.00$0.50DeepSeek-V4.1-Reasoner (97% lower)
Cached Input / 1M$7.50$0.01DeepSeek-V4.1-Reasoner lower
Output / 1M$60.00$2.50DeepSeek-V4.1-Reasoner lower
Context Window200k256kDeepSeek-V4.1-Reasoner (256k)
Max Generation Tokens100k384kDeepSeek-V4.1-Reasoner
Tokenizer FamilyOpenAI o200k_base (200k vocabulary)DeepSeek Byte-Level BPE (102k vocabulary)

Interactive Side-by-Side Cost Simulator

Live Delta
Input Tokens / Req2,500
Output Tokens / Req800
Daily Requests10,000
OpenAI o1
$22,837.50 / month
$0.0761 / request
DeepSeek-V4.1-ReasonerLOWER COST
$791.25 / month
$0.00264 / request
Selecting DeepSeek-V4.1-Reasoner saves $22,046.25 / month (96.5% savings) over OpenAI o1.

When to Choose OpenAI o1

Opt for OpenAI o1 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 $15/M input rate.

When to Choose DeepSeek-V4.1-Reasoner

Opt for DeepSeek-V4.1-Reasoner when looking for DeepSeek's tooling integration, specific context window depth (256k tokens), or when output generation volume favors its $2.5/M rate.