The exact percentage of retinol in the IOPE RETINOL RETI-JECTION™ SERUM is not specified in the reviews. However, the product is described as having a low concentration of retinol, which is suitable for first-time users and those with sensitive skin. Users have reported that it is gentle and does not cause significant irritation.

To obtain the precise percentage of retinol, please refer to the product's official description or contact the brand directly for more detailed information.

The IOPE RETINOL RETI-JECTION™ SERUM contains a low concentration of retinol, making it suitable for first-time users and those with sensitive skin. The specific percentage of retinol is not explicitly mentioned in the reviews, but it is noted that the product is gentle and designed to minimize irritation. Users are advised to start with a small amount and gradually increase usage as their skin builds tolerance.

For more detailed information on the exact retinol concentration, it would be best to refer to the product's official description or contact the brand directly.