AllocateGPT-5.5 vs Kimi K2.5
On provider list prices, Kimi K2.5 costs $0.50 per million input tokens against $5 for GPT-5.5: 10.0x apart. Output is $2.80 against $30 (10.7x).
GPT-5.5
Kimi K2.5Specifications and provider list prices from the Allocate catalog, checked 2026-07-21.
What the numbers say
Take 1,000,000 requests a month at 1,200 input and 350 output tokens each. That workload costs $1,580 a month on Kimi K2.5 and $16,500 on GPT-5.5 at list: a gap of $14,920, or 10.4x.
GPT-5.5 reads 400K tokens per request against 256K for Kimi K2.5, 1.5x the window. That decides which one can take whole documents without splitting them.
Choose Kimi K2.5 for
- Whole-document reasoning
- Long-context retrieval
- Open-weight fine-tuning
Common questions
Which is cheaper, GPT-5.5 or Kimi K2.5?
Kimi K2.5, on this workload shape. At list prices it is $0.50/$2.80 per million tokens in and out against $5/$30 for GPT-5.5. Billed on Allocate: $0.54/$3.00 against $5.35/$32.10.
Which has the bigger context window?
GPT-5.5: 400,000 tokens (400K) against 262,144 (256K) for Kimi K2.5.
Can I fine-tune GPT-5.5 or Kimi K2.5?
Kimi K2.5 publishes open weights (Not listed) and can be fine-tuned on your own data. GPT-5.5 is a closed model served over API; its weights are not available.
Related comparisons
Run the numbers on your workload
Or don’t choose. On Allocate a route name is the contract: point yours at one model today, swap to the other tomorrow, and compare them on your live traffic with per-token metering.