AI cover letter generator

Sign in

Sign in

How to Improve Your Cover Letter with AI

Coen de Waal
Coen de Waal

Founder of CareerToolbelt

(Step-by-step, beginner-friendly prompts)

Who this guide is for (and what you’ll need)

If you have a cover letter draft, this guide is for you. Maybe you are applying to your first role, exploring a career change, or simply polishing years of experience. AI can help you make your letter sharper, clearer, and more compelling.

To follow along, you will just need a few things: your draft cover letter, the job description (a quick copy/paste works), and your resume. If you also have extras like a portfolio link, a referral, or even a note on why this company caught your eye, AI can use that context to tailor your letter even more.

Why use AI for your cover letter?

AI has become much more than a grammar checker. Think of it as a smart, always-available writing coach that helps you:

  • Tighten sentences so recruiters actually read them instead of skimming
  • Turn vague claims into concrete impact ("managed a project" → "delivered 3 weeks early, cut costs 18%")
  • Fine-tune your tone whether you want it to sound confident, approachable, or professional, without clichés
  • Reflect keywords from the job post so your letter is ATS-friendly without keyword stuffing

In short: AI does not replace your voice, it amplifies it.

Core editing prompts (copy-paste)

If you are new to AI and not sure how to “prompt” yet, do not worry. A prompt is simply the instruction you give AI to edit or rewrite your text. You can copy the examples below word for word and paste them into your AI tool.

Do not know how to use an AI tool? Check out How to create a cover letter with AI.

Where you see text in square brackets (e.g. [paste], [insert here]), replace it with your own information. Each placeholder tells you what type of content should go there (for example: a draft, a list of highlights, or missing numbers).

1) Tighten the draft

Recruiters often skim quickly. A concise letter (under about 230 words) increases the chance they will read the whole thing instead of scanning or skipping.

Prompt to copy-paste:

Please edit this cover letter to under 230 words. Remove filler phrases but keep all important achievements.
Draft: [paste]

2) Sharpen achievements (with numbers)

Achievements with numbers are almost always stronger. Recruiters love to see scale, results, and impact. Metrics make your experience concrete and credible. Even small numbers (like time saved, users helped, or percentage improved) can make a big difference.

If you have metrics that show your impact (like revenue growth, cost savings, time saved, team size managed, etc.), you can provide them here. AI will then rewrite your achievements using those values.

➡️ If you do not have numbers handy, just skip this step.

Prompt to copy-paste:

Rewrite these achievements with metrics/outcomes I provide below.

Inputs:

  • Draft: [paste]
  • Metrics/outcomes: [paste values]

Example: Adding numbers to your cover letter

Here is a simple before-and-after to show how much difference adding context and numbers can make.

Before (no numbers):

Don't

Led a project to improve the onboarding process for new hires.

After (with provided numbers):

Do

Led a project that reduced new-hire onboarding time by 30%, saving the company 200 hours annually.

3) Tailor to the job post (ATS-friendly, not robotic)

Hiring managers and applicant tracking systems look for alignment between your letter and the role. Using keywords naturally shows you have paid attention and helps your letter pass ATS filters.

Prompt to copy-paste:

Edit this letter so it directly addresses the role’s top needs and includes relevant keywords naturally (no stuffing).
Job post: [paste]
Draft: [paste]

4) Calibrate tone and flow

Not every company expects the same style. A startup might value energy and creativity, while a law firm may prefer precision and formality.

Prompt to copy-paste:

Make this cover letter confident, warm, and professional. Avoid clichés like "passionate," "hard-working," or "fast-paced." Use clear, concrete language.

5) Add a personal hook (1–2 sentences)

Personalization proves you are not sending the same letter everywhere. Even one or two lines that connect your background to the company’s mission or recent work can make your application stand out.

Prompt to copy-paste:

Add 1–2 specific sentences connecting my background to this company’s mission, product, or recent news. Avoid generic praise and keep it concise.
Draft: [paste]
Context (why them, portfolio, referral): [paste]

6) Final proofread and polish

Even if AI usually writes grammatically correct text, it may still create clunky sentences, awkward phrasing, or miss subtle readability issues. If you do not want to follow all the earlier steps, or just want an extra safety net, you can ask AI for a quick once-over.

Prompt to copy-paste:

Proofread for grammar, spelling, and readability. Suggest any last improvements that increase clarity or impact without adding length.

AI Is a Conversation, Not a One-Off

Keep in mind: You don’t have to nail it on the first try. Think of AI as more of a conversation than a one-off command. If the draft comes back too long, just say “make this shorter but keep all numbers.” If it feels too stiff, try “rewrite with a warmer, more human tone.”

It’s also good to know that AI doesn’t always remember or apply everything you’ve said earlier in the way you’d expect. Sometimes instructions get overlooked, or the tool drifts a bit off track. If that happens, just remind it of your key points again — or even restart in a fresh chat with your draft and prompts.

One Prompt to Instantly Improve Your Cover Letter

Instead of the multiple prompts we shared earlier, you can also just use this one all-in-one prompt.
It takes care of shortening, polishing, tailoring, and personalizing your cover letter in a single step.

✅ How to use this

  1. Upload your resume file in the AI chat of your choice (don’t paste it).
  2. Copy the entire prompt below.
  3. Replace the placeholder text with your own.

📝 All-in-One Prompt

Please improve this cover letter by:
– Cutting it to under 230 words – Rewriting achievements with metrics/outcomes I provide (skip if none)Aligning it with the job description (natural keywords, no stuffing) – Adding 1–2 personalized sentences using my motivation/context – Setting the tone to confident, warm, and professional in first-person active voice

Inputs:

  • Draft cover letter: [PASTE COVER LETTER HERE]

  • Resume: See uploaded resume

  • Job posting: [PASTE JOB POSTING HERE]

  • Motivation/context: [PASTE WHY I WANT THIS ROLE / PORTFOLIO / REFERRAL HERE]

  • Metrics/outcomes (optional): [PASTE NUMBERS HERE OR LEAVE BLANK]

Ethical & practical AI tips

  • Truthfulness: never claim work you didn’t do.
  • Privacy: remove confidential client names unless public. Use “a Fortune 500 fintech” if needed.
  • Keeping it accurate: give AI your resume and job description so it edits based on your info, not guesses.

FAQs

Frequently asked questions

No, you don’t need a paid tool. While ChatGPT can help, CareerToolbelt is purpose-built for job seekers. It delivers optimised, ready-to-use results instantly, with tailored features and insights that ChatGPT doesn’t offer for the job search process.

Yes, personalized cover letters can make a big difference. A study by CareerBuilder found that 72% of hiring managers are more likely to interview candidates who submit customized cover letters.

Our tool helps you create tailored cover letters by analyzing your resume and the job description to highlight your relevant skills and experiences.

Writing a cover letter with CareerToolbelt's AI tool is simple:

  1. Enter Job Details: Add the job description.
  2. Upload Your Resume: If it's your first time, upload your resume.
  3. Pick Suggested Keywords: Choose which AI-suggested keywords are relevant to you.
  4. Edit the Result: Refine your cover letter using our AI editing tools.

To get started, visit CareerToolbelt's cover letter generator

Coen de Waal

Written by

Coen de Waal

Coen de Waal is the founder of CareerToolbelt, an AI-powered platform helping job seekers improve their resumes, cover letters, and job search strategies. Combining insights from hiring professionals with data on thousands of successful applications, he shares clear, data-driven advice to help people get hired in today’s job market.

Build Your Cover Letter with Our AI Generator Tool

Join other successful job seekers who already got hired with cover letters created with careertoolbelt.com

Try the AI Cover Letter Generator