Purpose: EDBreast gel is a new Fricke gel dosimeter, read by Magnetic Resonance Imaging, which composition includes a high amount of sucrose in order to lower diffusion effects. This paper aims at determining the dosimetric characteristics of this gel dosimeter. Methods: This characterization has been performed in high energy photon beams. The dose-response of the gel has been evaluated as well as its detection limit, its fading effects, the reproducibility of its response, and its stability over time. Its energy and dose-rate dependence has been investigated, and the overall dose uncertainty budget established. Once characterized, the dosimetry method has been applied to a simple irradiation case, with the measurement of the lateral dose profile of a 2 x 2 cm² field of a 6 MV photon beam. The results have been compared with microDiamond measurements. Results: EDBreast response exhibits a polynomial dose response on the 2 - 20 Gy range. It is more sensitive at low doses than the common Fricke gel dosimeters, but its sensitivity decreases with the dose enhancement, and the uncertainty of 8 % (k=1) at 20 Gy is higher than the requirement of quality controls in radiotherapy. However, the gel dose profile measurements, corrected for diffusion effects, show a good agreement with the microDiamond detector results, as the gamma-index passing rates were over 94 % using 2 % and 2 mm criteria. Conclusion: This work has characterized EDBreast gel dosimeter in an exhaustive way, and has proposed the good practices for its use.