AllocateDeepSeek V4 vs GPT-5.5
On provider list prices, DeepSeek V4 costs $1.74 per million input tokens against $5 for GPT-5.5: 2.9x apart. Output is $3.48 against $30 (8.6x).
DeepSeek V4
GPT-5.5Specifications 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 $3,306 a month on DeepSeek V4 and $16,500 on GPT-5.5 at list: a gap of $13,194, or 5.0x.
DeepSeek V4 reads 512K tokens per request against 400K for GPT-5.5, 1.3x the window. That decides which one can take whole documents without splitting them.
Choose DeepSeek V4 for
- Reasoning-heavy agents
- Long-document analysis
- Cost-sensitive production routes
Common questions
Which is cheaper, DeepSeek V4 or GPT-5.5?
DeepSeek V4, on this workload shape. At list prices it is $1.74/$3.48 per million tokens in and out against $5/$30 for GPT-5.5. Billed on Allocate: $1.86/$3.72 against $5.35/$32.10.
Which has the bigger context window?
DeepSeek V4: 512,000 tokens (512K) against 400,000 (400K) for GPT-5.5.
Can I fine-tune DeepSeek V4 or GPT-5.5?
No. Both are closed models served over API. If you want a model you can train and own, start from an open-weights base in the catalog.
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.