ChatGPT
Brainstorming angles, outlines, headlines and research summaries
Directory / AI Writing & Research
AI Writing & Research tools for Substack writers
AI assistants for brainstorming, outlining, critique and research. Use with care.
Claude
Long-document feedback, structural edits and drafting help
Perplexity
Quick research with cited sources
Sudowrite
Fiction writers publishing serialized stories
Pricing at a glance
| Tool | Best for | Pricing (checked 2026-10-18) |
|---|---|---|
| ChatGPT | Brainstorming angles, outlines, headlines and research summaries | Free; Plus $20/mo. |
| Claude | Long-document feedback, structural edits and drafting help | Free; Pro $20/mo or $17/mo billed annually. |
| Perplexity | Quick research with cited sources | Free; Pro $20/mo. |
| Sudowrite | Fiction writers publishing serialized stories | Hobby & Student $10/mo; Professional $22/mo; Max $44/mo; free trial. |
Prices change. Always confirm on the vendor's site.
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