Source-tracked model comparison

Grok 4.5 vs Kimi K3: 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: Grok 4.5 is estimated at $615.00 per month and Kimi K3 at $969.00 for 150,000 input tokens, 5,000 output tokens, and 2,000 monthly requests. Grok 4.5 is $354.00 lower under these assumptions. This does not identify a quality winner.
Current provider alternativesLong-context researchSources checked 2026-07-17 / 2026-07-17
Tracked facts

Pricing and model limits

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

FieldGrok 4.5Kimi K3
API access providerxAI APIKimi API
Model creatorxAIMoonshot AI
API model IDgrok-4.5kimi-k3
Input / 1M$2.00$3.00
Cached input / 1M$0.50$0.30
Output / 1M$6.00$15.00
Context window500,000 tokens1,048,576 tokens
Maximum outputUnavailable tokensUnavailable tokens
Accepted inputtext, imagetext, 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.

xAI

Grok 4.5

$615.00 / month
Input cost
$555.00
Output cost
$60.00
Per 1,000 calls
$307.50
Pricing profile
standard / short context
View model details
Moonshot AI

Kimi K3

$969.00 / month
Input cost
$819.00
Output cost
$150.00
Per 1,000 calls
$484.50
Pricing profile
standard
View model details

Cost result: Grok 4.5 is $354.00 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, caching, and context tiers 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.