Chemdle aims to provide players with curated and interesting problems. Now you can submit a puzzle of your own! Each accepted puzzle earns you three months of premium access (including archive access, hints, leaderboard, and more).

If this is your first time submitting, please read the guidance below. If you're a regular, click here to skip straight to the submission.

How To Use

Chemdles have a few key parts: the problem image, the structure of starting materials, intermediates, and products, and details about the problem including hints. Here's how to submit a Chemdle:

• First, draw the problem image, trying to make it look like a typical problem (include an arrow and a question mark. Click Get Image and Starting Materials to extract the image and all molecules drawn. You can make changes and press this again to update.
• Clear the sketcher and draw intermediates. Draw intermediates and press Add Intermediate(s) to extract the intermediate you've drawn. Do this for each reasonable intermediate. You can also draw multiple intermediates at once, all molecules in the sketcher will be extracted. Multiple intermediates are better as these show players they are on the right track. At least one per step is expected.
• Draw the product, then click Add Product. Only 1 product is allowed.
• Add hints - these are new to Chemdle in 2026 - they should not give the game away too easily, and each hint should be progressively more useful than the previous one. Add them in the order that players should see them.
• Enter puzzle details including a reference and link to the paper, and some notes about the puzzle - describe what is happening and anything interesting worth mentioning!
• When you are finished, check the details and press Submit.

What Next?

• You will receive a link to the review page for the puzzle you submitted - only you and select reviewers will be able to see this. Give it a try and make sure it plays as expected.
• Each submitted Chemdle will be reviewed (typically within a couple of days) and, if accepted, will be queued for play. Accepted submissions will automatically give you three months more Chemdle Premium.
• If you notice a problem after submitting, simply go to the review page and click reject, leaving a comment.

A Few Rules...

Please stick to the following rules:

• Puzzles should be of reasonable difficulty. A mixture of difficulties is encouraged, but try not to make it too easy (solved in one guess) or too hard (or impossible!)
• All puzzles must be published in either a reputable chemistry journal or a patent. Examples from books are fine, but please try to trace the original reference.
• Avoid overlapping structures - the images shown in the preview boxes are how they will appear to users. If there is a lot of overlapping 3D structure like spaghetti, it isn't likely to be clear to users.
• Keep any text and descriptions suitable for all audiences.

Tips

• These 2D and 3D buttons clean up structures (like the clean up feature in ChemDraw):
• Clicking reset sketcher will redraw the arrow and question mark. If you need the arrow to be longer, use this button then click and drag - it should snap to horizontal:
• Add text using the text button - this allows for rich text so you can subscript or insert symbols (e.g. ºC) as needed: