Which is cheaper, Claude Opus 4.1 (batch) or Claude Fable 5?

Claude Opus 4.1 (batch) is the cheaper of the two: one 1,000-word request costs about 16,972 toman, about 1.3× cheaper than Claude Fable 5.

Which one has the larger context window?

Claude Fable 5, with 1,000,000 tokens.

Claude Opus 4.1 (batch) vs Claude Fable 5

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, Claude Opus 4.1 (batch) comes out about 1.3× cheaper.

Feature	Claude Opus 4.1 (batch)	Claude Fable 5
Provider	Anthropic	Anthropic
Model id	anthropic/claude-opus-4.1:batch	anthropic/claude-fable-5
Context	200,000 tokens	1,000,000 tokens
Max output	32,000 tokens	128,000 tokens
Input / 1M tokens	2,175,938 toman	2,901,250 toman
Output / 1M tokens	10,879,688 toman	14,506,250 toman
≈ one 1,000-word request	16,972 toman	22,630 toman
Input caching	217,594 toman / 1M	290,125 toman / 1M
Image input	Yes	Yes
File input	Yes	Yes
Tool calling	Yes	Yes
JSON output	Yes	Yes
Reasoning mode	Yes	Yes

Which one for what?

Claude Opus 4.1 (batch)

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

16,972 toman per 1,000 words · Model page

Claude Fable 5

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

22,630 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": "anthropic/claude-opus-4.1:batch",
    "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="anthropic/claude-opus-4.1:batch",
    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: "anthropic/claude-opus-4.1:batch",
  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' => 'anthropic/claude-opus-4.1:batch',
    '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:    "anthropic/claude-opus-4.1:batch",
		Messages: []openai.ChatCompletionMessageParamUnion{openai.UserMessage("Introduce yourself in one sentence.")},
	})
	if err != nil {
		panic(err)
	}
	fmt.Println(resp.Choices[0].Message.Content)
}

model = "anthropic/claude-fable-5"

More comparisons: all pairs · model rankings · full catalogue

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