1. Introduction
2. The J-PLUS Survey
3. Methodologies
3.1. Two filters (2F) method
3.2. Three filters (3F) method
3.3. SED-fitting method
3.4. Measurements and error estimation
4. Testing the methodologies
4.1. Data sample
4.2. J-PLUS vs. SDSS
5. SED fitting routine: performance and error budget
5.1. Dependence on \( \mathbf{m}_{r^{\prime}} \)
5.2. Dependence on EW
5.3. Simulating observations at higher \( \mathbf{m}_{r^{\prime}} \)
5.4. Estimating the errors
6. Dust correction and [N ii] removal
6.1. Dust correction
6.2. [N ii] correction
6.3. Hα only measurements
6.4. Error budget
7. Summary and conclusions