# GPT-5.5 vs Inkling

On provider list prices, Inkling costs $1.87 per million input tokens against $5 for GPT-5.5: 2.7x apart. Output is $4.68 against $30 (6.4x). On Allocate both bill at list plus the 7% transaction fee.

## Specifications

| | GPT-5.5 | Inkling |
| --- | --- | --- |
| Lab | OpenAI | Thinking Machines |
| Access | API only | Open weights |
| Context window | 400K tokens | 1M tokens |
| List price, input | $5 / M tokens | $1.87 / M tokens |
| List price, output | $30 / M tokens | $4.68 / M tokens |
| Cached input | $0.50 / M tokens | $0.37 / M tokens |
| License | Proprietary API | Apache 2.0 |
| Fine-tunable | No | Yes |

Specifications and provider list prices from the Allocate catalog, checked 2026-07-08. Billed price is list plus the 7% transaction fee.

## What the numbers say

Take 1,000,000 requests a month at 1,200 input and 350 output tokens each. That workload costs $3,882 a month on Inkling and $16,500 on GPT-5.5 at list: a gap of $12,618, or 4.3x.

Inkling reads 1M tokens per request against 400K for GPT-5.5, 2.5x the window. That decides which one can take whole documents without splitting them.

## Choose GPT-5.5 for

- Complex tool-using agents
- Code generation
- General assistants

## Choose Inkling for

- The lower list price ($1.87 in / $4.68 out per M tokens)
- The longer context window (1M vs 400K tokens)
- Open weights you can fine-tune and own

## Common questions

### Which is cheaper, GPT-5.5 or Inkling?

Inkling, on this workload shape. At list prices it is $1.87/$4.68 per million tokens in and out against $5/$30 for GPT-5.5. Billed on Allocate: $2.00/$5.01 against $5.35/$32.10, list plus 7%.

### Which has the bigger context window?

Inkling: 1,000,000 tokens (1M) against 400,000 (400K) for GPT-5.5.

### Can I fine-tune GPT-5.5 or Inkling?

Inkling publishes open weights (Apache 2.0) and can be fine-tuned on your own data. GPT-5.5 is a closed model served over API; its weights are not available.

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[HTML page](https://allocate.network/compare/gpt-5-5-vs-thinkingmachines-inkling) · [GPT-5.5](https://allocate.network/models/gpt-5-5.md) · [Inkling](https://allocate.network/models/thinkingmachines-inkling.md) · [Machine-readable catalog](https://allocate.network/catalog.json)