Moving from OpenAI API to Anthropic Claude
A cost comparison and planning checklist. These are assessment steps, not vendor-specific migration instructions.
OpenAI API
Industry-standard foundation models with automatic prompt caching and vision.
$3.08 / month
GPT-4o mini
Official pricing · Checked 2026-10-06
Cost breakdown and exclusions
- Monthly subscription: $0
- Standard input tokens: $1.50
- Output completion tokens: $1.20
- Cached prompt tokens: $0.38
- Automatic 50% prompt caching discount applies to prompts with 1,024+ identical leading tokens.
- Fine-tuning, Batch API discounts, audio/realtime APIs, and image generation.
Anthropic Claude
Leading coding and analytical models with 90% prompt cache read discounts.
Not modeled
Claude 3.5 Haiku
Official pricing · Checked 2026-10-08
Cost breakdown and exclusions
- Claude 3.5 Haiku retired on February 19, 2026. This model is unavailable on the Claude API.
- Claude 3.5 Sonnet retired on October 28, 2025. This model is unavailable on the Claude API.
- This pricing model is not supported.
Recurring cost difference
A savings figure cannot be established for this workload.
Not calculated. Estimate migration labor, overlapping subscriptions, transfer charges and contract obligations before dividing those costs by any monthly savings.
What this comparison covers
Commercial API inference for generative language and reasoning models. Shared multi-tenant API endpoints, standard rate limits, and pay-as-you-go billing without committed use discounts or provisioned throughput. Fine-tuning, batch API discounts, embeddings, and audio generation are excluded.
Evaluating 2 products from 4 published in this category. USD monthly equivalents, before tax. Features and service compatibility need separate evaluation.
- Standard input tokens
- 10,000,000 tokens / month
- Output tokens
- 2,000,000 tokens / month
- Cached prompt tokens
- 5,000,000 tokens / month
Before you move
- This is a readiness assessment, not a verified vendor migration procedure.
- Use the source pricing and plan documentation: https://openai.com/api/pricing/
- Use the target pricing and plan documentation: https://platform.claude.com/docs/en/about-claude/model-deprecations
- Obtain the account permissions, data-owner approvals and tested backups needed for your chosen transfer method.
Modeled recurring cost
OpenAI API: $3.08/month
Anthropic Claude: Estimate unavailable
A price ranking is unavailable because one or both products lack an eligible estimate for this workload.
Requirements
GPT-4o mini
Claude 3.5 Haiku
Evaluate task quality, context limits, output format, latency and data-handling requirements on representative prompts; token prices do not establish model equivalence.
Your migration readiness checklist
Check items as you review them. Progress is kept only while this page is open.
Questions before you decide
Does a lower monthly estimate mean the migration pays for itself?
Not calculated. Estimate migration labor, overlapping subscriptions, transfer charges and contract obligations before dividing those costs by any monthly savings.
Is this a guaranteed migration procedure?
No. This assessment identifies decisions to verify with official provider documentation. It does not establish interoperability, data portability, zero downtime or a rollback guarantee.