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2 DeepSeek models in llmwise, on paid plans. DeepSeek V4 Pro passed 49 of 50 of our test prompts, the most of any DeepSeek model.

A real answer from our test runs

DeepSeek V4 Pro

Translate this note into German. Keep names, dates, times and room numbers exactly as they are. Team, the quarterly review with Dr. Okafor moves from Tuesday to Thursday, 16 October, at 09:15 in room B204. Please send your updated figures to Lena Brandt by Wednesday noon. The call link stays the same, and the meeting will end by 10:45 at the latest.

DeepSeek V4 Pro · passed our check · October 8, 2026

Team, das Quartalsreview mit Dr. Okafor verschiebt sich von Dienstag auf Donnerstag, 16. Oktober, um 09:15 Uhr in Raum B204. Bitte sendet eure aktualisierten Zahlen bis Mittwochmittag an Lena Brandt. Der Anruflink bleibt unverändert, und das Meeting endet spätestens um 10:45 Uhr.

DeepSeek V4 Pro needs a paid plan; the 5 free messages on sign-up are on Claude Haiku 5.5.

Start free

Facts about other apps checked September 28, 2026 against App Store: DeepSeek - AI Assistant. Updated October 14, 2026.

Short answer

DeepSeek V4 Pro passed the most of our test prompts, 49 of 50; DeepSeek V4.1 Flash 48 of 50. They're on paid plans; the 5 free messages you get on sign-up are on Claude Haiku 5.5.

The DeepSeek models in llmwise

Every DeepSeek model in llmwise: the free trial, Pro's count, a typical message at its API price, and our test results.

The DeepSeek models
Model	Free trial	On Pro	Typical message, API price	Our test prompts passed
DeepSeek V4 ProDeepSeek	No	250 a month	$0.0044	49 of 50 (20 of 20 hard)
DeepSeek V4.1 FlashDeepSeek	No	60 a day	$0.0020	48 of 50 (19 of 20 hard)

On Pro: the most messages a month on the model if the month goes to it alone, or a day's on an everyday model. The API price is a 4,000-token question with a 700-token answer at the model's list price as of October 2026; in llmwise you pay per message. Our tests: the 50 prompts of our test runs on October 15, 2026.

Every limit is published. Paid plans also have a monthly fair-use limit on AI cost: Plus $3.75, Pro $7.50, Max $20, Ultra $42, Studio $85. Using every message on your plan at typical sizes stays under it; very large messages and heavy research use it faster. Every limit, explained.

DeepSeek, job by job

Prompts passed on each of our 10 jobs, 5 prompts a job.

Prompts passed on each job, by model
Job	DeepSeek V4 Pro	DeepSeek V4.1 Flash
Coding	5 of 5	5 of 5
Writing	5 of 5	4 of 5
Math	5 of 5	5 of 5
Summarization	5 of 5	5 of 5
Data analysis	5 of 5	5 of 5
Customer support	4 of 5	4 of 5
Translation	5 of 5	5 of 5
SQL	5 of 5	5 of 5
RAG and answering from documents	5 of 5	5 of 5
Agents and tool use	5 of 5	5 of 5

When to pick which DeepSeek model

Among the DeepSeek models only: the one that passed the most of each job, and when others tie, the one that costs less.

Coding
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
Writing
DeepSeek V4 Pro, 5 of 5 passed (2 of 2 hard).
Math
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
Summarization
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
Data analysis
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
Customer support
DeepSeek V4 Pro, 4 of 5 passed (2 of 2 hard).
Translation
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
SQL
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
RAG and answering from documents
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.
Agents and tool use
DeepSeek V4.1 Flash, 5 of 5 passed (2 of 2 hard). DeepSeek V4 Pro passed as many; DeepSeek V4.1 Flash costs less.

DeepSeek on one prompt, side by side

The same hard coding prompt, “Parse CSV with quoted fields”, sent to DeepSeek V4 Pro and DeepSeek V4.1 Flash: DeepSeek V4 Pro passed and DeepSeek V4.1 Flash passed.

The prompt: Parse CSV with quoted fields (hard)

Write a JavaScript function parseCsv(text) that parses CSV text into an array of rows, each an array of strings.
- Fields are separated by commas, and rows by \n or \r\n.
- A field may be wrapped in double quotes. Inside quotes, commas and line breaks are part of the field, and "" stands for one double quote.
- A quote inside a field that doesn't start with one is an ordinary character.
- A line break at the very end of the text doesn't start a new row, and an empty string gives [].
Reply with the whole function in one ```javascript code block: plain JavaScript for Node.js 22, no imports, no TypeScript.

DeepSeek V4 Pro

Passed: All 8 tests passed.

```javascript
function parseCsv(text) {
  const rows = [];
  let row = [];
  let field = '';
  let fieldStarted = false;
  let inQuotes = false;

  for (let i = 0; i < text.length; i++) {
    const ch = text[i];

    if (inQuotes) {
      if (ch === '"') {
        if (text[i + 1] === '"') {
          field += '"';
          i++;
        } else {
          inQuotes = false;
        }
      } else {
        field += ch;
      }
      continue;
    }

    if (ch === '"' && !fieldStarted) {
      inQuotes = true;
      fieldStarted = true;
    } else if (ch === ',') {
      row.push(field);
      field = '';
      fieldStarted = false;
    } else if (ch === '\n') {
      row.push(field);
      field = '';
      fieldStarted = false;
      rows.push(row);
      row = [];
    } else if (ch === '\r') {
      row.push(field);
      field = '';
      fieldStarted = false;
      rows.push(row);
      row = [];
      if (text[i + 1] === '\n') {
        i++;
      }
    } else {
      field += ch;
      fieldStarted = true;
    }
  }

  if (fieldStarted || row.length > 0) {
    row.push(field);
    rows.push(row);
  }

  return rows;
}
```

494 tokens in, 8,886 out (8,561 of them reasoning) · 122.3 s · $0.0357 · 1 message on Pro · answered by deepseek/deepseek-v4-pro-0813 via Wafer · October 8, 2026

DeepSeek V4.1 Flash

Passed: All 8 tests passed.

```javascript
function parseCsv(text) {
  const rows = [];
  let row = [];
  let field = '';
  let inQuotes = false;
  let pending = false; // true if there is an in-progress field/row
  let i = 0;
  const n = text.length;

  while (i < n) {
    const ch = text[i];

    if (inQuotes) {
      if (ch === '"') {
        if (text[i + 1] === '"') {
          field += '"';
          i += 2;
        } else {
          inQuotes = false;
          i += 1;
        }
      } else {
        field += ch;
        i += 1;
      }
      continue;
    }

    if (ch === '"' && field === '') {
      // A quote only opens a quoted field when it is the first char of the field.
      inQuotes = true;
      pending = true;
      i += 1;
      continue;
    }

    if (ch === ',') {
      row.push(field);
      field = '';
      pending = true;
      i += 1;
      continue;
    }

    if (ch === '\n' || ch === '\r') {
      if (ch === '\r' && text[i + 1] === '\n') i += 1; // treat CRLF as one break
      row.push(field);
      rows.push(row);
      row = [];
      field = '';
      pending = false;
      i += 1;
      continue;
    }

    field += ch;
    pending = true;
    i += 1;
  }

  // A line break at the very end leaves "pending" false, so no empty trailing row.
  if (pending) {
    row.push(field);
    rows.push(row);
  }

  return rows;
}
```

522 tokens in, 3,473 out (3,074 of them reasoning) · 9.1 s · $0.0042 · 1 message on Pro · answered by deepseek/deepseek-v4.1-flash via Together · October 8, 2026

DeepSeek's own app

llmwise isn't DeepSeek's app. DeepSeek, DeepSeek's own, has a free tier too; in its words: “Experience seamless interaction with DeepSeek's official AI assistant for free!” (App Store: DeepSeek - AI Assistant, checked September 28, 2026).

Where your messages go

DeepSeek models are served only through OpenRouter, by endpoints that don't store or train on prompts. The Privacy Policy has the details.

More ways to chat

The other chat pages, each with its own models and test results.

Questions

Can I chat with DeepSeek for free?

Not DeepSeek itself: its models need a paid plan. DeepSeek V4 Pro and DeepSeek V4.1 Flash need a paid plan, from $20 a month. The free-message box on this page, when it shows, is answered by Claude Haiku 5.5, not by DeepSeek.

Is this the official DeepSeek app?

No. llmwise isn't made by DeepSeek and isn't affiliated with it: it offers DeepSeek's DeepSeek models next to 7 other AI families, in one chat. DeepSeek's own app has a free tier too; in its words: “Experience seamless interaction with DeepSeek's official AI assistant for free!” (App Store: DeepSeek - AI Assistant, checked September 28, 2026).

Which DeepSeek model should I use?

In our test runs on October 15, 2026, DeepSeek V4 Pro passed the most: 49 of 50 prompts. DeepSeek V4.1 Flash, an everyday model, passed 48 of 50 and counts against 60 a day on Pro. The cheapest per message, DeepSeek V4.1 Flash, passed 48 of 50. Start on the cheaper one and switch when an answer isn't good enough: the next model sees the whole chat.

Where do my DeepSeek messages go?

DeepSeek models are served only through OpenRouter, by endpoints that don't store or train on prompts.

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