Inkling (free) API: toman pricing and code
thinkingmachines/inkling:free
Free · shared capacityvisiontoolsreasoningaudioYou are billed for the usage the request actually reported. Prices follow the market.Pricing and top-ups
Inkling (free) example: reading an image into JSON
The example is picked from this model's own capabilities. Drop in your key and it runs as is.
# tip: a data URI works too — base64 the file and prefix it with data:image/jpeg;base64,
curl https://api.uttapen.ir/v1/chat/completions \
-H "Authorization: Bearer sk-up-…" \
-H "Content-Type: application/json" \
-d '{
"model": "thinkingmachines/inkling:free",
"messages": [{
"role": "user",
"content": [
{"type": "text", "text": "Return only the invoice number and the total, as JSON."},
{"type": "image_url", "image_url": {"url": "https://example.com/factor.jpg"}}
]
}]
}'import base64, json
from openai import OpenAI
client = OpenAI(base_url="https://api.uttapen.ir/v1", api_key="sk-up-…")
img = base64.b64encode(open("factor.jpg", "rb").read()).decode()
resp = client.chat.completions.create(
model="thinkingmachines/inkling:free",
messages=[{
"role": "user",
"content": [
{"type": "text", "text": "Return the invoice number, the date and the total as JSON."},
{"type": "image_url", "image_url": {"url": f"data:image/jpeg;base64,{img}"}},
],
}],
response_format={"type": "json_object"},
)
print(json.loads(resp.choices[0].message.content))import OpenAI from "openai";
import { readFileSync } from "node:fs";
const client = new OpenAI({ baseURL: "https://api.uttapen.ir/v1", apiKey: "sk-up-…" });
const img = readFileSync("factor.jpg").toString("base64");
const resp = await client.chat.completions.create({
model: "thinkingmachines/inkling:free",
messages: [{
role: "user",
content: [
{ type: "text", text: "Return the invoice number, the date and the total as JSON." },
{ type: "image_url", image_url: { url: `data:image/jpeg;base64,${img}` } },
],
}],
response_format: { type: "json_object" },
});
console.log(JSON.parse(resp.choices[0].message.content));What is Inkling (free) good for?
Inkling (free) comes from Thinking Machines; in uttapen you reach it with the model id "thinkingmachines/inkling:free". It accepts up to 1,048,576 tokens of input per call, so a long document or several source files fit in a single request. A single response can run to 262,144 tokens. Using it costs nothing. In exchange the capacity is shared, so during busy hours a request can come back empty-handed.
What you get on top of text in, text out: it reads images directly, which makes it a real option for invoices, forms and screenshots; it accepts audio input; it supports tool calling, so it can invoke your own functions with valid arguments; it has a reasoning mode that pays off on multi-step problems, maths and debugging. All of it works through the standard parameters of the official OpenAI SDK — no custom client, no wrapper. Keep in mind that reasoning tokens are output tokens and do appear on the bill.
Input runs at 0 toman per 1M tokens and output at 0 — output costs 0× input, so trimming the answer saves more than trimming the prompt. You are always charged for the usage the request actually reported, never for the estimate, and a failed request costs nothing.
The closest alternative with the same capabilities from a different provider is Dots3-Note Preview (free), and its context window is larger. Both run on the same key and the same code, so trying the other one is a single string change.
This id gets confused with "thinkingmachines/inkling", because the underlying model is the same. The difference is the suffix: "free" against the standard variant. Maximum answer length differs as well: 262,144 against 471,859 tokens. On parameters the other takes logit_bias, min_p, repetition_penalty, response_format.
Thinking Machines has 6 models in our catalogue; the cheapest is Inkling Small at 622 toman per thousand words and the dearest Inkling (batch) at 1,905. Among the less common parameters it accepts reasoning_effort — all through the standard request body. It does not support response_format, tool_choice, structured_outputs, which most models here do, so test before switching if your code relies on them. By context size the nearest option from another provider is DeepSeek V4 Flash 0423 at 1,048,576 tokens.
Where it makes sense: proving an idea works before you spend anything, logic puzzles and code review, pulling text and fields out of images, agents that reach out to APIs and databases, analysing a long document or codebase in one request.
Inkling is an open-weight multimodal mixture-of-experts model from Thinking Machines Lab, with 41B active parameters out of 975B total. It is designed for general-purpose reasoning, coding, agentic and tool-use systems,...
Three real jobs, priced on this model
Each figure is derived from the prices above and moves when they do.
| Job | Tokens | Cost |
|---|---|---|
| One chat turn with a medium history | 1,500 in + 400 out | 0 toman |
| Summarising a ten-page document | 4,000 in + 600 out | 0 toman |
| Classifying a thousand short rows | 120,000 in + 20,000 out | 0 toman |
Other variants of this model
Same core model, different execution terms and different price. This page is the free variant.
| Variant | Model id | Output / 1M | Context |
|---|---|---|---|
| standard | thinkingmachines/inkling | 1,175,006 | 1,048,576 |
| batch (cheaper, slower) | thinkingmachines/inkling:batch | 1,175,006 | 524,288 |
Put the variant's id verbatim in the model field; nothing else in your code changes.
Frequently asked
- How do I call Inkling (free) from Iran?
- Sign up with your mobile number, top the wallet up in toman, create an API key, then in the official OpenAI SDK point base_url at https://api.uttapen.ir/v1 and set model to "thinkingmachines/inkling:free". Nothing else in your code changes.
- What does Inkling (free) cost in toman?
- 0 toman per 1M input tokens and 0 toman per 1M output tokens; a 1,000-word request is around 0 toman. You pay for the usage that request actually reported, and a failed request costs nothing.
- How much input does Inkling (free) take?
- Up to 1,048,576 tokens per request, roughly 786k words. A single answer can reach 262,144 tokens.
- Does Inkling (free) support streaming and tool calling?
- Streaming (stream=true) works on every model here. This one supports tool calling in the standard OpenAI shape. Image input is accepted through image_url, as a data URI or a public URL.
- What are the limits on a free model?
- Free models have a daily per-user cap and their capacity is shared with everyone else. When the shared pool is exhausted the request is refused with a clear error and your wallet is untouched.