FixMyPrompt vs ChatGPT Custom Instructions
Built into ChatGPT — set persistent prompt context.
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/ FixMyPrompt vs ChatGPT Custom Instructions
Who is ChatGPT Custom Instructions?
Custom Instructions is a free ChatGPT feature where you set two text boxes — 'about you' and 'how you want responses formatted' — that apply to every chat. They give baseline context. They do not fix the specific prompt you're about to send.
Side-by-side comparison
| Axis | FixMyPrompt | ChatGPT Custom Instructions | Winner |
|---|---|---|---|
| Per-prompt fixing | Yes — analyzes the exact prompt | No — applies the same context to every chat | FixMyPrompt |
| Persistent identity context | No — stateless QA | Yes — set once, applies to all chats | Them |
| Scored rubric | Yes — 0–100 with weak-spot diagnosis | No | FixMyPrompt |
| Works with Claude/Gemini/Midjourney | Yes — model-agnostic | ChatGPT only | FixMyPrompt |
| Image prompts | Yes — dedicated rubric | No | FixMyPrompt |
| Cost | Free 3/day, pay-as-you-go from $2.99 | Free with ChatGPT account | Them |
When ChatGPT Custom Instructions wins
- You want the same context applied to every ChatGPT chat (job title, response style).
- You only use ChatGPT and don't need cross-model help.
When FixMyPrompt wins
- A specific prompt is failing and you need to know why.
- You use Claude, Gemini, or Midjourney alongside ChatGPT.
- You want to learn the rubric so you can write better prompts without a tool.
Bottom line
Use Custom Instructions to set who-you-are defaults once. Use FixMyPrompt when a specific prompt isn't producing the output you want. They're complementary, not competitors.
FAQ
If I set good Custom Instructions, do I still need FixMyPrompt?
Custom Instructions help your baseline, but they cannot rescue a vague or under-specified prompt for a specific task. They're complementary — use both.
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