How to use AI to write better online listings — fast
A practical guide for sellers on any platform: generate titles, descriptions, keywords, hashtags, and even product images using free AI tools — no technical experience needed.
Works on: Wix, WooCommerce, Shopify, eBay, Poshmark, Mercari, Vinted, Facebook Marketplace, Etsy, and more.
You already know AI exists. Maybe you’ve even tried ChatGPT for something random. But using it to write your listings? That’s where most sellers leave serious time and money on the table. A well-written listing with the right keywords and a clean image can be the difference between a sale and a scroll past — and AI can help you produce one in under five minutes.
The three AI tools you need to know
All three tools below have a free tier that is more than enough for writing listings. You do not need to pay for any of them to get results.
- Claude (Anthropic) — claude.ai — Excellent for structured, detailed descriptions. Follows multi-part instructions closely and handles titles, bullets, keywords, and hashtags in a single prompt. Great for longer listings on Shopify, WooCommerce, Etsy, and eBay.
- ChatGPT (OpenAI) — chatgpt.com — The most widely known option. GPT-4o (free) handles conversational, casual-tone platforms particularly well. Great for Facebook Marketplace, Mercari, and Poshmark.
- Gemini (Google) — gemini.google.com — Integrated with Google Search, which means it can help you understand what buyers are actually searching for. Useful for keyword research alongside description writing.
Which should you use? Any of the three will work for everything in this guide. Try all three with the same prompt and pick the output you like most. Most sellers settle on a favorite after just a few tries — there is no wrong answer.
Step 1: Give AI the right raw material
The quality of your listing depends entirely on what you tell the AI about your item. Before writing a single prompt, gather these details:
- What the item is — be specific (brand, model, size, color, material)
- Condition — new, like new, good, fair, and any flaws to disclose
- What makes it worth buying — features, benefits, what problem it solves
- Where you are selling — platform matters for tone and length
- Your price range — optional, but helps AI match tone to the buyer
Think of it like briefing a copywriter. The more specific you are, the less back-and-forth you need.
Step 2: Generate your listing title
Your title is the most important line in your listing. It is what search algorithms index and what buyers scan first. A good title is specific, keyword-rich, and readable.
Prompt template — listing title
Write 3 listing titles for the following item. Each title should be under 80 characters, include the most important search keywords, and be suitable for [PLATFORM]. Do not use clickbait or all-caps.
Item details: [PASTE YOUR ITEM DETAILS HERE]
Replace [PLATFORM] with your actual platform. Ask for 3 options so you can choose or mix the best parts.
Platform title limits: eBay: 80 characters. Etsy: 140. Shopify/WooCommerce: no hard limit, keep under 70 for SEO. Facebook Marketplace & Mercari: 100 characters. Poshmark: 50 characters.
Step 3: Generate your listing description
This is where AI really earns its keep. A full description that would take you 20 minutes to write takes AI about 10 seconds — and you just edit the result.
Prompt template — listing description
Write a product listing description for [PLATFORM]. Use a [TONE] tone. Include: a short opening hook, key features as bullet points, condition details, and a call to action at the end. Keep it under [LENGTH] words.
Item details: [PASTE YOUR ITEM DETAILS HERE]
Fill in [TONE] based on your platform. Use “friendly and casual” for Facebook Marketplace or Vinted, “professional and detailed” for eBay or WooCommerce, and “aspirational” for Poshmark or Depop.
As a length guide: eBay descriptions work best at 150–300 words. Poshmark at 80–150. Facebook Marketplace at 50–100. Shopify, WooCommerce, and Wix at 200–400. Etsy at 150–300.
Step 4: Generate keywords
Keywords are the terms buyers type into search boxes. On platforms like eBay, Etsy, and your own website, getting keywords right directly affects how often your listing appears.
Prompt template — search keywords
Generate 15 search keywords for the following item being sold on [PLATFORM]. Include a mix of broad terms (what the item is), specific terms (brand, model, size), and long-tail phrases (what a buyer might type when ready to buy). Return them as a comma-separated list.
Item details: [PASTE YOUR ITEM DETAILS HERE]
Long-tail keywords like “vintage leather brown bifold wallet mens slim” outperform generic ones like “wallet” because they match what buyers type when they are ready to purchase, not just browsing.
eBay keyword stuffing warning: Do not paste your keyword list directly into your eBay title as a wall of words. Use the most important 3–5 naturally in your title and weave others into your description. eBay’s search algorithm penalizes titles that read like keyword spam.
Step 5: Generate hashtags
Hashtags matter most on Poshmark, Instagram Shop, and Facebook. Etsy and eBay do not use them. For platforms where they count, AI can generate a targeted set in seconds.
Prompt template — hashtags
Generate 20 hashtags for a [PLATFORM] listing for the following item. Mix high-volume tags (broad reach), mid-volume tags (targeted buyers), and niche tags (engaged communities). Return them ready to paste, each starting with #.Item details: [PASTE YOUR ITEM DETAILS HERE]
Poshmark allows up to 25 tags per listing — mix brand names, style terms, and occasion tags. Instagram Shop allows up to 30 per post. For eBay and Etsy, skip hashtags entirely and focus on keywords instead.
Step 6: Generate a product image using free AI tools
A clean, professional product image significantly increases click-through rates. If you do not have a great photo — or want a lifestyle-style secondary image — free AI image generators can help.
Nano Banana (nanobana.ai)
Nano Banana is a free AI image generator well-suited to product shots. It produces clean, commercial-looking images without a paid subscription and is a good starting point for simple product-on-background images.
Other free options
- Adobe Firefly — High-quality, commercially safe images with a free credit tier. Great for lifestyle and context shots.
- Microsoft Designer / Bing Image Creator — Free with a Microsoft account. Powered by DALL-E. Fast and simple for basic product images.
- Canva AI (Magic Media) — Built into Canva, so you can generate an image and immediately resize and brand it for any platform in the same tool.
- Ideogram — Strong at text-in-image. Great if you need a product image that also includes readable labels or pricing overlays.
AI image prompt template
Product photography of [ITEM DESCRIPTION], placed on a [white/light wood/marble / neutral linen] surface, soft natural lighting, clean background, commercial product shot style, no hands, no text
Check your platform’s image rules: Some platforms (notably Poshmark and Depop) require that your primary listing photo show the actual item, not an AI-generated image. AI images work well as secondary photos and lifestyle shots — just not as the hero photo on platforms that require real photos.
The full workflow in six steps
- Gather your item details. Brand, model, condition, size, color, and any flaws. Plain text is fine.
- Open your AI tool of choice. Claude, ChatGPT, or Gemini. Free tier is sufficient.
- Run the master prompt below. Get title, description, keywords, and hashtags in one go.
- Edit the output. Adjust tone, fix inaccuracies, and add personal details that AI could not know.
- Generate your product image. Use Nano Banana or one of the other free tools above.
- Paste and publish. Copy each element into your listing fields. Done.
The master prompt — do it all at once
Once you are comfortable, use this single prompt to generate everything in one go:
Master prompt — full listing package
I am creating a product listing on [PLATFORM]. Please generate the following, clearly labeled:
- TITLE: 3 title options under 80 characters, keyword-optimized for [PLATFORM]
- DESCRIPTION: A [TONE] product description under [LENGTH] words with a hook, bullet-point features, condition notes, and a call to action
- KEYWORDS: 15 search keywords as a comma-separated list, mix of broad and long-tail
- HASHTAGS: 20 hashtags ready to paste (only include if relevant for [PLATFORM])Item details:- Item: [NAME / BRAND / MODEL]- Condition: [CONDITION AND ANY FLAWS]- Key features: [LIST FEATURES]- Price: [YOUR PRICE]
Pro tip — save your master prompt as a template. Copy it into a notes app or Google Doc with your platform and tone already filled in. Next time you list something, just swap in the item details. A full listing in under two minutes.
Applies to all major selling platforms · AI tool features are accurate as of May 2026.
