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

Claude Haiku 4.5 vs OpenAI o1

Side-by-side technical and economic comparison between Anthropic's Claude Haiku 4.5 and OpenAI's OpenAI o1.

Endpoint Availability & Transition Notice

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

Core Technical & Pricing Comparison
MetricClaude Haiku 4.5OpenAI o1Advantage
Provider OrganizationAnthropicOpenAI
Standard Input / 1M$1.00$15.00Claude Haiku 4.5 (93% lower)
Cached Input / 1M$0.10$7.50Claude Haiku 4.5 lower
Output / 1M$5.00$60.00Claude Haiku 4.5 lower
Context Window200k200kEqual
Max Generation Tokens8.2k100kOpenAI o1
Tokenizer FamilyAnthropic Claude BPE (~65k vocabulary)OpenAI o200k_base (200k vocabulary)

Interactive Side-by-Side Cost Simulator

Live Delta
Input Tokens / Req2,500
Output Tokens / Req800
Daily Requests10,000
Claude Haiku 4.5LOWER COST
$1,612.50 / month
$0.00537 / request
OpenAI o1
$22,837.50 / month
$0.0761 / request
Selecting Claude Haiku 4.5 saves $21,225.00 / month (92.9% savings) over OpenAI o1.

When to Choose Claude Haiku 4.5

Opt for Claude Haiku 4.5 when your engineering requirements prioritize Anthropic's ecosystem, specific tokenizer efficiencies (Calibrated Claude Tokenizer (±3%)), or when your expected prompt-to-completion ratios favor its $1/M input rate.

When to Choose OpenAI o1

Opt for OpenAI o1 when looking for OpenAI's tooling integration, specific context window depth (200k tokens), or when output generation volume favors its $60/M rate.