OpenAI vs Anthropic Pricing – Full API Cost Comparison

Which is cheaper: OpenAI or Anthropic? The answer depends on your use case. Compare pricing across standard models (GPT-4o vs Claude 3.5 Sonnet) and reasoning models (o1/o3 vs Claude 3 Opus).

Quick Comparison: Flagship Models

Model	Input (per 1M)	Output (per 1M)	Context	Best For
GPT-4o	$2.50	$10.00	128K	General purpose, fast
Claude 3.5 Sonnet	$3.00	$15.00	200K	Long docs, reasoning
GPT-4o-mini	$0.15	$0.60	128K	High volume, cost-sensitive
Claude 3.5 Haiku	$0.80	$4.00	200K	Fast, lightweight

Key differences:

• GPT-4o is cheaper for both input ($2.50 vs $3.00) and output ($10 vs $15)
• Claude 3.5 Sonnet has a larger context window (200K vs 128K)
• GPT-4o-mini is the cheapest option for high-volume use
• Claude 3.5 Haiku offers good value with Claude’s larger context

Reasoning Models: o1/o3 vs Claude 3 Opus

For complex reasoning tasks, both providers offer premium models:

Model	Input (per 1M)	Output (per 1M)	Context	Notes
o1	$15.00	$60.00	128K	Deep reasoning, math, code
o1-mini	$3.00	$12.00	128K	Faster reasoning, lower cost
o3-mini	$1.10	$4.40	200K	Newest reasoning model
Claude 3 Opus	$15.00	$75.00	200K	Highest quality Claude

When to use reasoning models:

• Complex multi-step problems
• Mathematical proofs or calculations
• Code that requires careful planning
• Tasks where accuracy > speed

When to stick with standard models:

• High-volume applications
• Real-time chat
• Simple Q&A or summarization
• Cost-sensitive projects

When to Choose OpenAI

Choose OpenAI if:

• You need the lowest cost for high-volume use
• Your use case is input-heavy (analysis, summarization)
• You need fast response times
• You’re building consumer-facing applications
• You need reasoning models (o1/o3) for complex tasks

Best for: Cost-sensitive applications, high-volume processing, real-time chat, complex reasoning

When to Choose Anthropic

Choose Anthropic if:

• You need to process very long documents (200K context)
• You prioritize consistent quality over cost
• You’re building enterprise applications
• You need superior long-context understanding
• You want prompt caching to reduce costs

Best for: Document analysis, enterprise applications, long-form content

Real-World Cost Examples

Scenario 1: High Volume Chat (GPT-4o-mini vs Claude 3.5 Haiku)

• 50M input tokens/month, 10M output tokens/month
• GPT-4o-mini: $7.50 + $6 = $13.50/month
• Claude 3.5 Haiku: $40 + $40 = $80/month
• Winner: GPT-4o-mini (83% cheaper)

Scenario 2: Document Analysis (GPT-4o vs Claude 3.5 Sonnet)

• 10M input tokens/month, 2M output tokens/month
• GPT-4o: $25 + $20 = $45/month
• Claude 3.5 Sonnet: $30 + $30 = $60/month
• Winner: GPT-4o (25% cheaper)

Scenario 3: Complex Reasoning (o1 vs Claude 3 Opus)

• 1M input tokens/month, 500K output tokens/month
• o1: $15 + $30 = $45/month
• Claude 3 Opus: $15 + $37.50 = $52.50/month
• Winner: o1 (14% cheaper)

Scenario 4: Budget Reasoning (o1-mini vs Claude 3.5 Sonnet)

• 5M input tokens/month, 2M output tokens/month
• o1-mini: $15 + $24 = $39/month
• Claude 3.5 Sonnet: $15 + $30 = $45/month
• Winner: o1-mini (13% cheaper)

Use the calculator above to see costs for your specific usage patterns.

Hidden Costs to Consider

Prompt Caching

Anthropic offers prompt caching that can significantly reduce costs for repeated inputs (like system prompts). If you’re sending the same context repeatedly, Claude may be cheaper than list prices suggest.

Rate Limits

OpenAI’s rate limits are tier-based. If you’re on a lower tier, you might need to pay more to upgrade. See OpenAI Rate Limits for details.

Context Window Usage

Claude’s 200K context window means you can fit more in a single request. With GPT-4o’s 128K limit, you might need multiple requests for very long documents, increasing costs.

How to Use

1. Enter your monthly token usage in the calculator above
2. Click Calculate to see costs for all models
3. Compare side-by-side across providers

The calculator shows costs for 50+ models across all major providers, updated with the latest pricing.

FAQ

Is OpenAI or Anthropic cheaper?

For standard models, OpenAI is generally cheaper. GPT-4o costs $2.50/$10 per 1M tokens vs Claude 3.5 Sonnet at $3.00/$15. For reasoning models, o1 ($15/$60) is slightly cheaper than Claude 3 Opus ($15/$75) for output-heavy use cases.

Should I use reasoning models (o1/o3) or standard models?

Use reasoning models for complex tasks requiring multi-step thinking: math, coding, analysis. For simple chat, Q&A, or high-volume applications, standard models (GPT-4o, Claude 3.5 Sonnet) are faster and cheaper.

Which model has the best value for high volume?

GPT-4o-mini ($0.15/$0.60) offers the best value for high-volume applications. It’s 5-20x cheaper than flagship models while still being capable for most tasks.

Does Claude’s larger context window justify the higher cost?

It depends on your use case. If you need to process documents longer than 128K tokens, Claude’s 200K context window may be worth the 20-50% price premium. For most applications under 128K tokens, GPT-4o offers better value.

What about Google Gemini?

Gemini 1.5 Pro ($1.25/$5 per 1M tokens) and Gemini 1.5 Flash ($0.075/$0.30) are often cheaper than both OpenAI and Anthropic. Use the calculator above to compare all three providers.

Is this tool free?

Yes, completely free with no signup required. Calculate costs for any usage pattern instantly.

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