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Historical model (legacy). The rates below are the last recorded rates, not a recommendation for a new deployment.

GPT-5.6 Luna API Pricing

GPT-5.6 Luna costs $0.20 per 1M input tokens and $1.20 per 1M output tokens. These rates were last verified on .

Moving off GPT-5.6 Luna?

Newer version: GPT-6 Luna · 55.6% cheaper (provider has not retired GPT-5.6 Luna)

Same token usage, 3:1 input:output, standard list rates · excludes cache, batch and fast mode. Not a quality or compatibility claim. Full calculator →

OpenAI small general text pricing history

USD · units shown per rate
● Small
  1. Input: $0.10 / 1M tokensOutput: $0.50 / 1M tokens
    Rate first observed
    Latest
    Verified 2026-11-12
  2. Input: $0.20 / 1M tokensOutput: $1.20 / 1M tokens
    Rate first observed
    Available · older version
    Verified 2026-11-12
    1 recorded price changes
    • Input: $0.20 / 1M tokens · Output: $1.20 / 1M tokens — observed Jul 31, 2026
    • Input: $1.00 / 1M tokens · Output: $6.00 / 1M tokens — observed Jun 28, 2026 (first recorded)
  3. Input: $0.75 / 1M tokensOutput: $4.50 / 1M tokens
    Rate first observed
    Available · older version
    Verified 2026-11-12
  4. Input: $0.20 / 1M tokensOutput: $1.25 / 1M tokens
    Rate first observed
    Deprecated · 2027-04-01
    Verified 2026-11-12
  5. Input: $0.25 / 1M tokensOutput: $2.00 / 1M tokens
    Rate first observed
    Deprecated · 2026-12-11
    Verified 2026-11-12
  6. Input: $0.05 / 1M tokensOutput: $0.40 / 1M tokens
    Rate first observed
    Deprecated · 2026-12-11
    Verified 2026-11-12
  7. Input: $0.40 / 1M tokensOutput: $1.60 / 1M tokens
    Rate first observed
    Deprecated · 2027-01-14
    Verified 2026-11-12
  8. Input: $0.10 / 1M tokensOutput: $0.40 / 1M tokens
    Rate first observed
    Shut down
    Verified 2026-11-12
  9. Input: $0.15 / 1M tokensOutput: $0.60 / 1M tokens
    Rate first observed
    Deprecated · 2027-01-14
    Verified 2026-11-12

Newest first. Release dates describe the model, not when today's rates took effect. Observations show when we recorded rates, not launch pricing. Image and text token meters are separate; no fixed image-token savings mix is assumed. How we verify

Published rates and billing units

Billing dimensionUSD list price
Input / 1M tokens$0.20
Cached input / 1M tokens$0.02
Cache write (30 minutes) / 1M tokens$0.25
Requests above 272,000 input tokens: Input / 1M tokens$0.40
Requests above 272,000 input tokens: Cached input / 1M tokens$0.04
Requests above 272,000 input tokens: Cache write (30 minutes) / 1M tokens$0.50
Requests above 272,000 input tokens: Output / 1M tokens$1.80
Output / 1M tokens$1.20
Batch: Input / 1M tokens$0.10
Batch: Cached input / 1M tokens$0.01
Batch: Output / 1M tokens$0.60
Batch: Requests above 272,000 input tokens: Input / 1M tokens$0.20
Batch: Requests above 272,000 input tokens: Cached input / 1M tokens$0.02
Batch: Requests above 272,000 input tokens: Output / 1M tokens$0.90

Verified 2026-11-12 · Official source · Pricing methodology. Taxes, optional services and account-specific discounts are not included.

Cost examples

These examples use published list prices only. They exclude taxes, enterprise discounts, minimum charges, retries, batch discounts, and provider-specific billing rules.

1M input + 1M output

$2.20

A direct per-million comparison against every other text model.

100K input + 25K output

$0.05

A compact chat, summarization, or analysis workload.

10M input + 2M output

$7.60

A monthly production estimate for heavier RAG or agent traffic.

75% cached input + 250K output

$0.58

Cached input is about 90% cheaper than standard input at list price.

Calculator for GPT-5.6 Luna

Enter your own input, output, and cached-token assumptions. This calculator is preloaded with only GPT-5.6 Luna, so the result stays focused on this model.

Input cost

$0.40

Output cost

$1.80

Total

$2.20

Long-context rates apply because this request exceeds 272,000 input tokens.

Price history

input moved from $1.00 to $0.20 and output moved from $6.00 to $1.20 across 137 daily snapshots.

When to use GPT-5.6 Luna

Good fit

  • code generation, debugging, and agentic development work where output quality affects engineering time
  • high-volume routing, classification, extraction, summaries, and fallback traffic
  • long-document and repository-scale prompts where context window matters

Be careful with

  • blind migration without testing your own prompts, latency, and failure modes

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