Which is cheaper, Qwen3 Next 80B A3B Thinking or Qwen3.5-35B-A3B?

Qwen3 Next 80B A3B Thinking is the cheaper of the two: one 1,000-word request costs about 509 toman, about 1.2× cheaper than Qwen3.5-35B-A3B.

Which one has the larger context window?

Qwen3 Next 80B A3B Thinking, with 262,144 tokens.

Qwen3 Next 80B A3B Thinking vs Qwen3.5-35B-A3B

Both sit behind the same key and the same code on uttapen — the only thing that changes is the model string, so you can run each of them against your own workload without touching anything else. On cost, Qwen3 Next 80B A3B Thinking comes out about 1.2× cheaper.

Feature	Qwen3 Next 80B A3B Thinking	Qwen3.5-35B-A3B
Provider	Qwen (Alibaba)	Qwen (Alibaba)
Model id	qwen/qwen3-next-80b-a3b-thinking	qwen/qwen3.5-35b-a3b
Context	262,144 tokens	262,144 tokens
Max output	235,929 tokens	16,384 tokens
Input / 1M tokens	43,519 toman	90,664 toman
Output / 1M tokens	348,150 toman	362,656 toman
≈ one 1,000-word request	509 toman	589 toman
Input caching	No	45,332 toman / 1M
Image input	No	Yes
File input	No	No
Tool calling	Yes	Yes
JSON output	Yes	Yes
Reasoning mode	Yes	Yes

Which one for what?

Qwen3 Next 80B A3B Thinking

Multi-step problems, maths, and tracking down a bug
Whole documents or a codebase in a single request
Agents that call your own APIs and database

509 toman per 1,000 words · Model page

Qwen3.5-35B-A3B

Multi-step problems, maths, and tracking down a bug
Whole documents or a codebase in a single request
Reading screenshots, invoices, and scanned forms
Agents that call your own APIs and database

589 toman per 1,000 words · Model page

Run both with the same code

Swap the model value between the two ids and send the same request twice; what each answer cost comes back in the X-Uttapen-Cost-Toman header.

curl https://api.uttapen.ir/v1/chat/completions \
  -H "Authorization: Bearer sk-up-…" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen/qwen3-next-80b-a3b-thinking",
    "messages": [{"role": "user", "content": "Introduce yourself in one sentence."}],
    "stream": true
  }'

from openai import OpenAI

client = OpenAI(
    base_url="https://api.uttapen.ir/v1",
    api_key="sk-up-…",
)

stream = client.chat.completions.create(
    model="qwen/qwen3-next-80b-a3b-thinking",
    messages=[{"role": "user", "content": "Introduce yourself in one sentence."}],
    stream=True,
)
for chunk in stream:
    print(chunk.choices[0].delta.content or "", end="", flush=True)

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://api.uttapen.ir/v1",
  apiKey: "sk-up-…",
});

const stream = await client.chat.completions.create({
  model: "qwen/qwen3-next-80b-a3b-thinking",
  messages: [{ role: "user", content: "Introduce yourself in one sentence." }],
  stream: true,
});
for await (const chunk of stream) {
  process.stdout.write(chunk.choices[0]?.delta?.content ?? "");
}

<?php
// composer require openai-php/client guzzlehttp/guzzle
$client = OpenAI::factory()
    ->withBaseUri('https://api.uttapen.ir/v1')
    ->withApiKey('sk-up-…')
    ->make();

$result = $client->chat()->create([
    'model' => 'qwen/qwen3-next-80b-a3b-thinking',
    'messages' => [['role' => 'user', 'content' => 'Introduce yourself in one sentence.']],
]);
echo $result->choices[0]->message->content;

package main

import (
	"context"
	"fmt"

	"github.com/openai/openai-go"
	"github.com/openai/openai-go/option"
)

func main() {
	client := openai.NewClient(
		option.WithBaseURL("https://api.uttapen.ir/v1"),
		option.WithAPIKey("sk-up-…"),
	)
	resp, err := client.Chat.Completions.New(context.Background(), openai.ChatCompletionNewParams{
		Model:    "qwen/qwen3-next-80b-a3b-thinking",
		Messages: []openai.ChatCompletionMessageParamUnion{openai.UserMessage("Introduce yourself in one sentence.")},
	})
	if err != nil {
		panic(err)
	}
	fmt.Println(resp.Choices[0].Message.Content)
}

model = "qwen/qwen3.5-35b-a3b"

More comparisons: all pairs · model rankings · full catalogue

base_url = https://api.uttapen.ir/v1