Which free AI helps most with ENEM essay writing in 2026
It comes every year: ENEM approaches, pressure increases, and doubt about how to write a good essay takes over. The good news is that in 2026, free artificial intelligence tools have reached a level of maturity that can really help you, whether to understand the essay-argumentative structure, receive feedback on your texts, or build sociocultural knowledge. The bad news is that the supply is large, confusing, and full of promises that don’t always hold up in practice.
This guide compares the main free AIs available in Brazil today, explains how each can be used specifically for ENEM essay writing, and points out which makes the most sense for each student profile. The question that guides everything here is not “which AI is most powerful,” but rather “which AI helps you achieve a perfect score.”
Quick comparison: the main free AIs for essay writing
Before going into details, it’s worth having an overview side by side. The tools below are all accessible in Brazil, with no mandatory cost for basic use, and work in Portuguese.
| Tool | Company | Free plan | Language | Strength for essay writing |
|---|---|---|---|---|
| ChatGPT (GPT-4o) | OpenAI | Yes, with usage limits | Fluent Portuguese | Detailed feedback and grading board simulation |
| Gemini | Yes | Fluent Portuguese | Integration with Google Docs and updated knowledge | |
| Copilot | Microsoft | Yes (via Edge/Bing) | Fluent Portuguese | Real-time web access, good for research |
| Claude (Sonnet) | Anthropic | Yes, with daily limit | Reasonable Portuguese | Careful textual analysis and coherence |
| Le Chat (Mistral) | Mistral AI | Yes | Functional Portuguese | Speed and shorter responses |
ChatGPT: the most versatile, but requires knowing how to use it
The ChatGPT with GPT-4o model continues to be, in 2026, the most known reference and, for ENEM essay writing, the most versatile in the free plan. You can request corrections following the five official ENEM criteria (competencies 1 to 5), simulate a grading board, and request suggestions for thematic knowledge on a specific subject.
The point of attention is that the free plan applies usage limits after a certain amount of consecutive messages, and you may fall back to less capable models during peak times. OpenAI doesn’t disclose exact limits in a stable way, so behavior can vary. In practice, for study sessions of 20 to 30 minutes, this rarely becomes a problem.
To get the best out of ChatGPT for essay writing, the secret lies in the prompt (instruction you type to the AI). Instead of writing “correct my essay,” write something like: “Evaluate this text as an ENEM grader, analyzing each of the five competencies separately, pointing out specific errors and suggesting how to fix them.” The difference in results is enormous.
How to use ChatGPT in practice for ENEM
- Paste your complete essay in the conversation.
- Request evaluation competency by competency (C1 to C5).
- Ask for an estimated score for each competency, with justification.
- Request suggestions on how to improve the intervention proposal (C5 is often the weak point for many candidates).
- Rewrite the pointed-out sections and ask for a second round of analysis.
Gemini: the best for those already using Google
The Gemini, from Google, has a significant practical advantage for students: it integrates with Google Docs. This means you can write your essay directly in the text editor you probably already use and invoke the AI within the document itself, without needing to copy and paste anything.
Another strong point of Gemini is access to more recent information. Since Google keeps the model connected to updated sources, it tends to have fresher knowledge about current topics, which helps a lot when looking for arguments and data to enrich your text. For ENEM, where topics like public health, environment, and technology usually appear, this makes a difference.
Gemini also understands Portuguese naturally and responds well to requests for textual analysis. The caveat is that in very technical analyses of standard Portuguese (grammar, agreement, verb government), it can be less accurate than ChatGPT. It’s worth combining the two: Gemini for research and structure, ChatGPT for fine grammatical correction.
Copilot: real-time research is the differentiator
The Copilot, from Microsoft, is accessible directly through the Edge browser or the copilot.microsoft.com website, without needing to create an account for basic use. It uses OpenAI models underneath, but with an important difference: it accesses the internet in real-time.
For ENEM essay writing, this has a very specific and valuable use: research. You can ask “What were the main news about social inequality in Brazil in 2025 and 2026?” and receive answers with real sources. Using recent data and facts in your text, when relevant to the topic, contributes to competency 2 (mastery of world knowledge).
Copilot is not the best option for detailed essay correction, because it tends toward shorter and less analytical responses. But as a support tool for researching arguments and building sociocultural knowledge, it stands out among free options.
Claude: the most careful with text
The Claude, from Anthropic, is less popular in Brazil but deserves attention. According to Anthropic itself, the model was trained with a focus on following instructions carefully and producing more careful and less “generic” analyses. In practice, this translates to essay feedback that tends to be more specific and less repetitive than other AIs.
Claude’s free plan (Sonnet model) has a daily message limit, which can be restrictive for long study sessions. Portuguese is also functional, but noticeably less natural than ChatGPT or Gemini at times. For those wanting a second opinion on their own text, however, Claude is a good bet, precisely because it doesn’t tend to “praise” what’s bad just to please.
Strategy: combining AIs to maximize results
None of these tools need to be used exclusively. The most efficient approach for ENEM 2026 is to combine the strengths of each one.
- Research and topics: Copilot (web access) or Gemini
- Essay draft and structure: ChatGPT with well-crafted prompt
- Competency-by-competency correction: ChatGPT or Claude
- Final grammar review: ChatGPT with specific instruction for standard Portuguese errors
- Integration with text editor: Gemini in Google Docs
This combination requires no spending. All these tools have free plans sufficient for the kind of use an ENEM student needs, as long as you don’t spend hours on end in the same session without breaks.
If you’re thinking of using a tablet to study with these tools, device choice also matters. A comparison like iPad 11 vs Galaxy Tab S10 FE can help you decide which large screen makes the most sense for long study and writing sessions.
What AI won’t do for you (and this is critical)
There’s a real risk that needs to be stated clearly: using AI to write the essay instead of you is counterproductive. ENEM evaluates your ability to argue, not the machine’s. If you just copy what the AI suggests, you arrive at the test without having developed the skills the graders expect.
The correct use is different: AI as a tool for training and feedback. You write, the AI corrects, you learn from the mistakes, you rewrite. This cycle, repeated consistently, is what generates real score improvement. Think of AI as a personal tutor available 24 hours, not as an automatic text generator.
Another important point: AIs make mistakes. They can suggest incorrect data, cite sources with imprecisions, or make wrong grammatical analyses. Always verify factual information in reliable sources before using it in your text.
Frequently asked questions about free AI for ENEM essay writing
Is it allowed to use AI to train for ENEM essays?
Yes, using AI to train outside the test is completely allowed and, done well, is very effective. What’s not allowed, of course, is any external help during the actual in-person test. Training with AI happens at home, in preparation.
Can AI give exactly the same score as the ENEM graders?
Not with guaranteed accuracy. AIs can estimate scores by competency based on official criteria, but human grading by the board has nuances that no tool has completely replicated so far. Use AI scores as trend references, not as absolute values.
Do I need to pay to access the best features?
For focused ENEM essay writing use, the free plans of ChatGPT, Gemini, and Copilot are sufficient. Paid plans offer more messages per day, more powerful models, and extra features, but aren’t necessary for a basic cycle of writing, feedback, and rewriting.
Which AI is best for someone starting from zero in essay writing?
For those who have never trained essay-argumentative writing, ChatGPT with a well-constructed prompt is the most didactic starting point. Ask it to explain the text structure before you start writing, then use competency-by-competency feedback to adjust. Gemini is a good alternative if you already use the Google ecosystem.
What to do now to arrive prepared
Start today, not the week before ENEM. The cycle of writing, receiving feedback, and rewriting needs repetition to work, and a week isn’t enough to internalize the grading board’s criteria.
Set one topic per week, research with Copilot or Gemini, write the essay without AI help, and only then request feedback. This method simulates real test conditions and still takes advantage of everything free tools have to offer. In 2026, technology is on your side, but whoever writes the essay is still you.