Be careful before buying

Some platforms sell NFTs that you can lose at any time.

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NFT assets can be non-persistent

The storage method can have a low persistence & decentralization level.

Buy NFTs safely

After auditing how the NFT is coded, we measure the trust level you can have in NFT platforms.

See all scores

Effective grading scheme

Adapted to each type of platform, the grading is based on persistence, decentralization and the ease of retrieving NFT assets.

See the grading scheme

100% independent

No ads, no influence for brands. No one can pay OpenGem to advertise their platform on our website

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How to be audited

If you want your project to be audited, just add it to the queue by submitting here, it’s free. Regarding the line, you’ll need to wait ~90 days to be audited.

A 2 ETH donation will bring your project to first place in the line. In that way, an audit can be done in ~5 days.


Check if you really own your NFT

The higher the score, the more persistent the NFT assets.