How to Write a Cover Letter With AI (Free, No Signup)

The first time I asked an AI to write me a cover letter, I typed "write a cover letter for a marketing job" and hit enter. What came back was four paragraphs of confident, polished nothing. It opened with "I am writing to express my strong interest in the position of," which is the writing equivalent of a handshake from someone staring at their phone. I deleted it and felt slightly worse about the whole thing.

So I stopped asking AI to write the letter and started using it differently. The shift that mattered: don't ask the tool to produce a cover letter from thin air. Feed it the specific raw material only you have, then boss it around. Do that and you get something that sounds like you on a decent day. Skip it and you get the thing a hiring manager has already read 300 times this week.

Here's the whole process, prompts included.

What a cover letter is actually for

A cover letter isn't a summary of your resume. The resume already lists what you did. The letter answers a different question — why you, for this job, at this company, right now. It connects your evidence to their need, which a bullet list can't really do.

That framing also tells you what the AI needs from you. Leave out the "why this company" and the "here's my proof" and the model will paper over the gaps with generic enthusiasm. Generic enthusiasm is exactly what reads as machine-written. So the work is mostly in what you bring to the chat, not the chat itself.

Step 1: Gather your inputs before you open the chat

Three things, every time. Get them together first so you're not improvising halfway through.

The job description. Paste the whole thing. The exact phrases a company reaches for — "cross-functional," "own the roadmap," "scrappy" — tell you what they care about, and you want the AI echoing their language instead of generic industry mush.

Your resume, or a quick experience dump. The model needs to know what you've actually done. If your resume is tight, paste it. If not, a few lines per role does the job.

Two or three concrete achievements with real specifics. This is the part everyone skips and it's the one that matters most. Not "improved sales" but "rebuilt the onboarding email sequence and cut first-month churn from 19% to 12% over a quarter." The AI can't invent these. It can only sharpen what you hand it. Vague material in, vague letter out — every time, no exceptions.

If your resume itself needs work before any of this, fix that first — see the best free AI for resume writing. A strong resume makes the cover letter easier because the achievements are already worded.

Step 2: The structure that works

You don't have to dictate this, but knowing it helps you judge whether the output is any good. A solid cover letter is short. Three or four short paragraphs, comfortably under a page.

If the AI hands you five long paragraphs, cut. Hiring managers skim. Shorter and sharper beats longer and complete, and it isn't close.

Step 3: The prompt that gives you a usable first draft

Don't ask for a cover letter. Ask for a tailored one with constraints. Paste your three inputs, then this:

"Here is a job description, my resume, and three achievements with real numbers. Write a cover letter of no more than 250 words, in four short paragraphs. Open with a specific hook about why this company and role interest me — do not start with 'I am writing to apply.' Use one of my achievements as the main proof point and tie it to a need in the job description. Keep the tone warm and direct, like a smart colleague, not formal or corporate. Do not invent any facts, numbers, or experience I haven't given you. Avoid clichés like 'results-driven,' 'passionate,' 'team player,' and 'fast-paced environment.'"

The word cap, the banned-cliché list, and the "do not invent" line do most of the lifting. Without them the model defaults to long and bland, which is its comfort zone.

Step 4: Inject your voice

A first draft from AI is structurally fine and emotionally dead. This is where you make it yours. Three quick moves.

Give it a voice sample. Paste a paragraph you actually wrote — an old email, a Slack message you were a little proud of — and say:

"Here's how I actually write. Rewrite the cover letter to match this voice: more like this, less like a press release. [paste your sample]"

This is the single biggest upgrade in the whole process. AI is genuinely good at copying a register once it has an example to copy. It just won't do it unprompted.

Then add one human detail. Tell it something true — you've used the company's product for two years, you've been following their open-source project, one specific thing about the role that actually interests you. Then:

"Work this detail into the opening naturally, without making it sound like flattery: [your detail]"

And read the thing out loud. If a sentence makes you wince or sounds like nobody you've ever met, cut it. Your ear is more reliable here than the model's fluency. Fluent and hollow is the default failure mode.

Step 5: Tailor per company (the part most people skip)

The entire point of a cover letter is that it's specific. Send the same one to ten companies and you've thrown away the format. But you don't have to start from zero each time. Keep your strong base draft, then:

"I'm sending a version of this letter to a different company. Here's their job description and one thing I genuinely admire about them. Rewrite the opening paragraph and adjust the body to match their priorities, keeping my voice and my achievements the same. [paste new job description + your detail]"

Two minutes per application, and each letter reads like it was written for that company. Because it was.

The mistakes that give AI away

These are the tells hiring managers clock without thinking about it.

• Over-formal register. "I would be most grateful for the opportunity to further discuss my candidacy." Nobody talks like this. Tell the AI to loosen up.
• Cliché stacking. "Results-driven professional," "proven track record," "passionate about excellence." Empty calories. Ban them in the prompt, then scan for survivors, because some always slip through.
• Symmetry that's too perfect. AI loves three-item lists and tidy balanced sentences. A bit of variation in rhythm reads more like a person.
• Praise with no substance. "Your company's innovative culture inspires me." Inspires you how? If you can't say, cut it.
• Restating the resume. A paragraph that just relists jobs is wasted space. Every paragraph should add something the resume can't.
• Length. A 500-word cover letter tells the reader you didn't edit. Half that is plenty.

A quick before-and-after

Here's the AI's default opener, untouched:

"I am writing to express my strong interest in the Product Manager position at your company. With my proven track record and passion for innovation, I am confident I would be a valuable addition to your team."

And here's the kind of opener those same prompts produce once you feed in a real detail — imagine an applicant to a scheduling-software company who actually uses the product:

"I've been running a volunteer team on your scheduling tool for the past year, and the way you handle recurring shifts is the cleanest I've found. So when the Product Manager role opened, I paid attention — because shipping exactly this kind of workflow software is what I want to be doing."

Same role, same prompts. The second one got there by feeding the AI a true, specific detail and banning the clichés. That's the entire trick — the substance has to come from you.

Try it now

Open Smillee AI, paste in a job description, your resume, and three real achievements, and run the Step 3 prompt. Then give it a paragraph of your own writing and ask it to match your voice. It's free, no signup, and you'll have a tailored draft in a couple of minutes — one that sounds like you instead of like every other applicant in the stack.

— Maya