GPT-4o mini vs GPT-5.6 Luna
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
| Specification |
by OpenAI
|
by OpenAI
|
|---|---|---|
| Overview | ||
| Status | Current budget | Current mid tier |
| Released | Jul 18, 2024 | Jul 9, 2026 |
| Pricing per million tokens | ||
| Input | $0.150/Mtok | $0.200/Mtok |
| Output | $0.600/Mtok | $1.20/Mtok |
| Blended avg | $0.262/Mtok | $0.450/Mtok |
| Cached input | $0.075/Mtok | $0.020/Mtok |
| Specifications | ||
| Context window | 128K tokens | 1M tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimage
|
textimage
|
| Benchmarks sources: Artificial Analysis / Vellum LLM Leaderboard | ||
| Independent composite scores measured for both models — each on its own scale | ||
| AA Agentic Index | 1 | 46.9 |
| AA Intelligence Index | — | 52.3 |
| AA-Omniscience Index (−100–100) | — | -10.3 |
| GDPval-AA v2 | — | 1569.1 ELO |
| Per-benchmark results published for GPT-5.6 Luna only — no independent per-benchmark scores exist for GPT-4o mini yet | ||
| Avg benchmark score | — | 90.7 |
| Perf / dollar | — | 201.6 |
| GPQA Diamond | — | 92.3 |
| SWE-Bench Verified | — | 93 |
| Terminal-Bench 2.1 | — | 84.3 |
| HumanEval | — | 93 |
| Providers | ||
| Available from |
OpenAI — $0.150/$0.600/Mtok
|
OpenAI — $0.200/$1.20/Mtok
|
Cost at scale
1M tokens · 50/50 input/output| Volume | GPT-4o mini | GPT-5.6 Luna | Savings |
|---|---|---|---|
| 1M tokens | $0.26 | $0.45 | $0.19 (42.2%) |
| 10M tokens | $2.62 | $4.5 | $1.88 (41.8%) |
| 100M tokens | $26.25 | $45 | $18.75 (41.7%) |
| 1000M tokens | $262.5 | $450 | $187.5 (41.7%) |
When to pick which
distilled from the pricing and spec data above- cost dominates: $0.262/Mtok blended vs $0.450 — 41.7% less on the same 50/50 token mix
- your workload re-reads context (agents, RAG, long chats): cached input costs $0.020/Mtok — 90% off its list input price
- you need the longer context: 1M tokens vs 128K (8.2×)
Price movement
recorded changes since we began tracking each model · last checked Aug 28, 2026| Model | Changes | Latest move | Old → new $/M |
|---|---|---|---|
| GPT-4o mini | 0 | — no move | Stable since we began tracking — no change recorded |
| GPT-5.6 Luna | 1 | price cut on Aug 1, 2026 | $1/$6 → $0.2/$1.2/Mtok |
The cheaper option here — GPT-4o mini costs $0.262/Mtok blended on OpenAI.
Summary
GPT-4o mini by OpenAI costs $0.150/Mtok input and $0.600/Mtok output, with a 128K-token context window. It supports text, image input.
GPT-5.6 Luna by OpenAI costs $0.200/Mtok input and $1.20/Mtok output, with a 1M-token context window. It supports text, image input.
On a blended cost basis, GPT-4o mini is 41.7% cheaper than GPT-5.6 Luna.
The two aren't directly comparable on average benchmark score: GPT-5.6 Luna has published per-benchmark results, while GPT-4o mini does not yet — it is measured today on independent composites (see the table above).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.