Judy was 24 when she entered the Police Academy (9 years at the beginning of the first film + 15 years time skip), and we don't know how long does boot camp last but it doesn't look like a short training, so by the time Zootopia 2 has happened and ended (looking at Nick's shirt) she could well be 25.
As a bonus fact, Judy calculates Nick's age to being around 32 during the tax evasion scene (confirmed by director Byron Howard), so their age gap is about 8 years. Judy was born the same year Nick was bullied and muzzled by the local Junior Ranger Scouts.