Source-tracked model comparison

gpt-5.6-luna vs Gemini 2.5 Pro: which costs less for a practical API workload?

Compare verified pricing and model limits for API pricing and workload fit across providers. The cost example uses a long-context research workload and does not assume equal model quality.

Direct cost answer: Gemini 2.5 Pro is estimated at $441.25 per month and gpt-5.6-luna at $333.00 for 150,000 input tokens, 5,000 output tokens, and 2,000 monthly requests. gpt-5.6-luna is $108.25 lower under these assumptions. This does not identify a quality winner.
low priorityobserveSources checked 2026-07-12 / 2026-07-13
Tracked facts

Pricing and model limits

Prices are USD per 1M tokens under each model's verified default profile.

FieldGemini 2.5 Progpt-5.6-luna
ProviderGoogleOpenAI
API model IDgemini-2.5-progpt-5.6-luna
Input / 1M$1.25$1.00
Cached input / 1M$0.125$0.10
Output / 1M$10.00$6.00
Context window1,048,576 tokens1,050,000 tokens
Maximum output65,536 tokens128,000 tokens
Accepted inputtext, image, video, audio, pdftext, image
Example workload

Long-context research cost scenario

150,000 input and 5,000 output tokens per request, 2,000 monthly requests, and 10% cached input.

Google

Gemini 2.5 Pro

$441.25 / month
Input cost
$341.25
Output cost
$100.00
Per 1,000 calls
$220.63
Pricing profile
standard / short context
View model details
OpenAI

gpt-5.6-luna

$333.00 / month
Input cost
$273.00
Output cost
$60.00
Per 1,000 calls
$166.50
Pricing profile
standard / short context
View model details

Cost result: gpt-5.6-luna is $108.25 lower per month for these assumptions. This is a price comparison, not a model-quality ranking.

StackLens assessment

Questions to answer before choosing

  • Which model meets the required quality threshold on representative inputs?
  • How do output length, retries, and caching change the measured cost?
  • Which provider and deployment path fit the team's operational requirements?
Workload caveat

What this estimate leaves out

Models whose tracked context window is below the scenario input are excluded from the compatible-model table.

Latency, reliability, output quality, retries, regional processing, and provider-specific tool charges can change the practical decision.