# How to make ChatGPT Instagram posts that look designed

[Canonical HTML page](https://gradiently.design/guide/chatgpt-instagram-posts)

ChatGPT writes a good caption in seconds. The picture is where most posts fall apart. Here is a flow that gets you both, with prompts you can copy and the sizes Instagram wants.

## The short version

- ChatGPT is strongest at the words of an Instagram post: the hook, the slide text, the caption and the alt text.
- A ChatGPT Instagram post works best when the brief names the audience, the one thing to say, the format and the tone.
- Images generated with words baked into the pixels often misspell them and cannot be edited, so keep text as a separate layer.
- The standard Instagram feed post is 1080×1350 pixels, and a Story or Reel is 1080×1920.
- Connecting a design tool to ChatGPT through MCP lets it place its words on a real, editable design instead of describing one.

To make a **ChatGPT Instagram post**, use ChatGPT for the words and a design tool for the picture. Brief it with your audience, the single point of the post and the format, ask for a short hook plus a caption, then set those words as real text on a 1080×1350 design. The shortcut people try first, asking ChatGPT to generate the whole image, tends to give you misspelt letters you cannot fix. Better still, connect a design tool to ChatGPT so it can build the post itself.

## What ChatGPT is good at, and where it stops

ChatGPT is a writer first. It is quick at turning a messy idea into a hook, cutting a caption down, suggesting ten angles for the same announcement and rewriting for a different tone. It is weaker at the visual half. Its image generation produces a flat picture: the text inside is drawn as pixels, the size may not match Instagram's frame, and every change means generating again. Why that happens is covered in [why AI images get text wrong](https://gradiently.design/guide/ai-text-in-images).

### ChatGPT on its own

- Strong hooks, captions and hashtags
- Generated images with text drawn as pixels
- Letters that can come out misspelt or warped
- One flat file, regenerated for every change
- Looks that resemble everyone else's AI posts

### ChatGPT with a design tool

- The same strong words
- Words set as real, editable text
- Spelling exactly as written
- Change a date without starting again
- Your own brand colours, fonts and background

## Step 1: give ChatGPT a brief it can work with

Vague prompts produce vague posts. The fix is a short brief with four things: who the post is for, the one thing it should say, the format, and how you sound. Paste this, fill in the brackets and keep it in a note so every post starts the same way.

```text
You are writing an Instagram post for [business], which sells [product] to [audience].

The one thing this post must say: [message].
Format: [single portrait post / 5 slide carousel / Story].
Tone: [calm and plain / warm and funny / precise], never salesy.

Give me:
1. Three hook options, each under 8 words, for the image itself.
2. One supporting line under 12 words.
3. A caption of 2 to 4 short sentences ending with one clear action.
4. Alt text describing the image for screen readers.
5. Five specific hashtags, no generic ones like #love.
```

A reusable brief. The word limits matter: text on an image has to be read in about a second.

## Step 2: separate the words on the image from the caption

The most common mistake is putting the caption on the picture. The image carries a few words that stop the scroll; the caption carries the detail. Ask ChatGPT for each part separately, as the brief above does, and you will get text sized for where it lives. [Writing copy for visuals](https://gradiently.design/guide/writing-copy-for-visuals) goes deeper on the difference.

| Part | Where it goes | Good length |
| --- | --- | --- |
| Hook | Large type on the image | 3 to 8 words |
| Supporting line | Small type under the hook | One short phrase |
| Caption | Under the post | 2 to 4 sentences, one action |
| Alt text | Accessibility settings when posting | One plain description |
| Hashtags | End of the caption | A few specific ones |

Ask ChatGPT for each part on its own line, so nothing meant for the caption ends up on the image.

## Step 3: pick the right Instagram size

Tell ChatGPT the format in the brief, because a Story hook can be longer than a square one, and design at the exact size Instagram expects. The portrait post takes the most room in the feed, which is why it is the default for most brands. The full list lives in [Instagram post size](https://gradiently.design/guide/instagram-post-size).

- Portrait post 1080×1350: 1080 × 1350
- Square 1080×1080: 1080 × 1080
- Landscape 1080×566: 1080 × 566
- Story and Reel 1080×1920: 1080 × 1920

Instagram's four frames, to scale. Portrait is the one to choose when in doubt.

## Step 4: turn ChatGPT's words into a design

You have three ways to get from copy to a finished post. Copy the text into any design tool and lay it out by hand, which works but repeats the same chores every time. Ask ChatGPT's image generator for a background only, with no words in it, then add your text on top in an editor. Or connect a design tool directly, so ChatGPT does the layout for you.

That third route uses MCP, the open standard that lets assistants use real tools. Gradiently works inside ChatGPT this way: once connected with a scoped API key, ChatGPT can search Marks, read your brand and create designs that open in the Studio as normal, editable pages, without spending Gradiently credits. The words stay real text, the background is your Mark, and legibility is handled for you because the Mark moves its calmest region behind the words. Setup is in [designing with ChatGPT](https://gradiently.design/guide/design-with-chatgpt) and the [developer docs](https://gradiently.design/developers/mcp).

1. **Create a key** In Gradiently, an owner or admin opens Settings › API and agents and creates a key scoped to what ChatGPT should do.
2. **Add the connector** Add Gradiently as a custom MCP connector wherever your ChatGPT plan and workspace allow it, using the snippet from Settings.
3. **Ask in plain words** For example: make a portrait Instagram post and a matching Story announcing our Saturday tasting, using our brand.
4. **Open and adjust** Each design opens in the Studio, where you can nudge a word, swap a photo and export.

## A worked example: one bakery announcement

Say a neighbourhood bakery is starting Sunday opening. The brief names locals within walking distance, one message (we are now open on Sundays), a portrait post plus a Story, and a warm, plain tone. ChatGPT offers hooks such as “Now open Sundays”, “Sunday bread, finally” and “Seven days a week now”. The owner picks the first, keeps the supporting line “From 8am, from this week” and puts the caption under the post.

A portrait Instagram post for a bakery reading Now open Sundays, with opening time underneath

The portrait feed post: hook large, one supporting line, nothing else on the image.

A vertical Instagram Story version of the bakery announcement with the words centred

The same words as a Story, kept in the middle band away from Instagram's interface.

Notice what is missing from the image: the caption, the hashtags, the address. Those belong under the post. For carousels, ask ChatGPT for one sentence per slide and read [Instagram carousel design](https://gradiently.design/guide/instagram-carousel-design) before you lay them out.

## Check these before you post

- Read every word on the image aloud. If ChatGPT invented a detail, such as a date or an offer, fix it now.
- Look at the post at thumbnail size on your phone. The hook should still read.
- Keep text out of roughly the top and bottom 250 pixels of a Story, where Instagram's interface sits. [Instagram Story size](https://gradiently.design/guide/instagram-story-size) shows the safe zone.
- Add the alt text ChatGPT wrote in Instagram's accessibility settings when posting.
- Rewrite any phrase that sounds like every other AI caption. Your own turn of phrase is the part people remember.

If you want a bank of briefs for other kinds of posts, [AI prompts for social media](https://gradiently.design/guide/prompts-for-social-media) has fifty that produce usable results.

## FAQ

### Can ChatGPT make Instagram posts?

It writes the words very well and can generate images, but text drawn inside a generated image can come out misspelt and cannot be edited. For a finished post, set its words as real text in a design tool, or connect one to ChatGPT.

### What is the best prompt for an Instagram caption in ChatGPT?

Name the audience, the one thing the post must say, the format and the tone, then ask for a hook, a short caption ending in one action, alt text and a few specific hashtags.

### What size should a ChatGPT Instagram post be?

Design feed posts at 1080×1350 pixels for portrait or 1080×1080 for square, and Stories or Reels at 1080×1920.

### Can I connect a design tool to ChatGPT?

Yes, where your ChatGPT plan allows custom MCP connectors. Gradiently connects this way with a scoped API key, and the designs ChatGPT makes open in the Studio for editing.