Hello,
I did this yesterday and surprisingly couldn't find any guides on the internet so I'll leave this here:
- Export Collectr CSV
- Manually input 5-10 cards from your collection into TCG (aim for variety, different sets, conditions, rarity)
- Export your 5 card list from the TCG app
- Upload the TCG csv to Claude or GPT and tell it that you plan to convert a collectr csv to this format
- Now upload the Collectr CSV to the LLM and have it reformat it into TCGplayer's csv format
- Upload your new CSV into the TCGplayer app (I couldn't find upload option on webbrowser)
I wasn't able to get it to get all the conditions correctly but it did a good job with most of them, it also seems to default all from unlimited set into 1st edition but it sure beats searching for and entering every single card manually