Claude Sonnet 5.5 vs Gemini 3.1 Pro Preview
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 Sonnet 5.5 comes out about 17% cheaper.
| Feature | Claude Sonnet 5.5 | |
|---|---|---|
| Provider | Anthropic | |
| Model id | anthropic/claude-sonnet-5.5 | google/gemini-3.1-pro-preview |
| Context | 1,000,000 tokens | 1,048,576 tokens |
| Max output | 128,000 tokens | 65,536 tokens |
| Input / 1M tokens | 692,439 toman | 692,439 toman |
| Output / 1M tokens | 3,462,194 toman | 4,154,632 toman |
| ≈ one 1,000-word request | 5,401 toman | 6,301 toman |
| Input caching | 34,622 toman / 1M | 69,244 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 Sonnet 5.5
- 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
5,401 toman per 1,000 words · Model page
Gemini 3.1 Pro Preview
- 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
6,301 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-sonnet-5.5",
"messages": [{"role": "user", "content": "Introduce yourself."}],
"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-sonnet-5.5",
messages=[{"role": "user", "content": "Introduce yourself."}],
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-sonnet-5.5",
messages: [{ role: "user", content: "Introduce yourself." }],
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-sonnet-5.5',
'messages' => [['role' => 'user', 'content' => 'Introduce yourself.']],
]);
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-sonnet-5.5",
Messages: []openai.ChatCompletionMessageParamUnion{openai.UserMessage("Introduce yourself.")},
})
if err != nil {
panic(err)
}
fmt.Println(resp.Choices[0].Message.Content)
}model = "google/gemini-3.1-pro-preview"
Frequently asked
- Which is cheaper, Claude Sonnet 5.5 or Gemini 3.1 Pro Preview?
- Claude Sonnet 5.5 is the cheaper of the two: one 1,000-word request costs about 5,401 toman, about 17% cheaper than Gemini 3.1 Pro Preview.
- Which one has the larger context window?
- Gemini 3.1 Pro Preview, with 1,048,576 tokens.
- Can I use Claude Sonnet 5.5 and Gemini 3.1 Pro Preview with one API key?
- Yes. An uttapen key reaches every model unless you gave it an allowed-models list, and each request is charged in toman to the same wallet; only the model value changes.
More comparisons: all pairs · model rankings · full catalogue
base_url = https://api.uttapen.ir/v1