GPT-6 Luna (via OpenAI API)
Translation with OpenAI's small GPT-6 Luna model, priced from OpenAI API token rates rather than per character.
Our token-to-character assumptions give an estimate of $0.185 per million characters, or about $0.09 through the Batch API. Non-English sources and non-Latin targets can use more tokens and cost more. EU regional-processing endpoints add 10% for models released on or after 5 March 2026. Test translation quality and terminology on your own content before choosing Luna for volume work.
- Headquarters
- 🇺🇸 United States
- Parent jurisdiction
- 🇺🇸 United States
- EU self-serve plan
- Available; check eligible plans and regions
- GDPR DPA
- Yes
- Billing
- payg
- Open source
- No
- Website
- openai.com
- Source last checked
- 2026-10-06
- Pricing evidence
- Modeled rates
Pricing
Published rates converted using workload assumptions. Read the notes. Token-to-character conversion assumes English source, short prompts and European-language output. Quality and retries are not priced. How to read these estimates.
| 1M additional characters |
|---|
| $0.185 |
Allowances, plan limits & calculation details
Rates are shown at their recorded precision. A zero means no charge in this calculation; the vendor may charge for things we leave out. See the notes for usage assumptions and currency conversions.
- Base fee / month
- $0
- Included characters / month (millions)
- 0
- 1M additional characters
- $0.185
Derived from token prices: $0.10 per 1M input tokens, $0.50 per 1M output tokens (standard tier). 0.35 x $0.10 + 0.30 x $0.50 = $0.035 + $0.15 = $0.185 per 1M characters. Assumptions (shared by all LLM-derived rows): English source at ~4 characters per token, so 1M characters = 250k source tokens; a ~200-token prompt per 2,000-character chunk adds 500 x 200 = 100k tokens, giving 350k input tokens per 1M characters; output for European target languages ~1.2x the source = 300k tokens. Cost per 1M characters = 0.35 x input price + 0.30 x output price (per 1M tokens). Non-Latin target languages (CJK, Arabic, Hindi) and non-English sources can use noticeably more tokens. The Batch API halves prices (~$0.09/M chars). The larger GPT-5.4 mini ($0.75/$4.50) costs 0.35 x 0.75 + 0.30 x 4.50 = $1.61/M chars. EU regional processing (data residency) endpoints add a 10% uplift for models released on or after 2026-03-05.
Managed alternatives
At 50M characters / month. Adjust usage and requirements.
GPT-6 Luna (via OpenAI API): $111/yr estimated.
No cheaper managed estimate matches your filters. Adjust your usage or compare with your actual contract bill.
The price difference leaves out migration costs, operating costs and any features you’d need to replace.
Self-hosted options
Operating cost is not estimated. These options are not counted as savings against managed services.
Want a European-owned provider? See European alternatives to GPT-6 Luna (via OpenAI API) among european machine translation providers.
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Found a wrong rate or plan restriction? Report a correction with a current source.