I'm pretty sure that s1 and s2 take place within the same year meaning that Adrien turned 14 within the same year as Marinette so it's likely that there's about 5 months difference in birthdays. Going by the assumption that a year passes every two seasons then that would mean that Adrien turned 15 towards the beginning of s3 while Marinette celebrated her 15th birthday towards the end of the season.

That means that during s1, Adrien had recently turned 14 while Marinette was 13.

During s2, Adrien is still 14 and Marinette also turns 14.

During s3, Adrien is 15 and Marinette is 14 and probably turned 15 right before Ladybug.

During s4, they will both be 15

Ehh good:)

Adrien is 14-15

Adrien turned 14 in episode 2,bubbler. Season 2 is right after season 1,in Gorizilla Gabriel refers to him as 14.

If you do the math from christmaster-season 3 ep.24 it also proves he is 14.

Tourmei on tumblr:

so if marinette has planned adrien’s next 35 birthday presents then gets an idea for his 50th birthday present, before that point she had planned adrien’s 15th through 49th birthdays. (49-15=34, but since both 15 and 49 are counted, the range includes 35 presents.)

so adrien is 14.

(if the writers did their math carefully and the numbers stay consistent in different dubs.)

Season 4 is right after season 3 as we can see in the new episode Truth,so he could be turning 15 this season but for now he's 14

@Marinettesbakery Watch the writers not stay consistent 😒

Didn't season 4 episode 1 of Miraculous come out on the 3rd of April

They are both 14 we see both of their 14th birthdays and less then a year has passed since Adrien’s birthday because his mom has been missing about a year and he didn’t become a superhero right after she disappeared

Yea they are both 15-16

Time is moving very slowly in this Series. During S4’s “Dearest Family” Marinette’s grandfather Rolland stated that she was still only 14. So Adrien would still be 14 or 15 at this point.

Both Adrien and Marinette are still 14 as seasons one through four take place within one school year!!

He is actually 14 throughout all of S1 to S4 and will probably continue to be 14 in S5 as long as there is no time skip. Here is all the evidence I’ve found but it is pretty long so you can skip to the end if you’d like:)

• In “Orgins- Part 1” (S1), Adrien Agreste and Marinette Dupain-Cheng both received the miraculous at age 13.

• In the S1 episode “The Bubble,” Adrien turns 14.

• The episodes “Mr.Pigeon” (from the first season) and “Style Queen” ( from season 2) show that Marinette wins a hat making contest for the Gabriel brand. It is said that her hat will be featured on next photoshoot. In Style Queen, Adrien models Marinette’s hat and it is heavily implied that it is the 1st time it is being showcased to the public. This can be shown by Marinette’s fear of judgement by both the attendees of Gabriel’s show and famous fashion critic, Audrey Bourgeois.

• The fifth episode in S2 is “Befana.” This is when Marinette turns 14.

• In “Gorizilla” (S2), Gabriel confirms that Adrien is still a 14 year old.

• In “Catalyst,” ( S2 finale- Pt.1) Nathalie says that Lila has been holding negative feelings towards Ladybug for months. This is a reference to the episode “Volpina”. Nathalie’s direct words are as follows: Lila has been harboring her rage against Ladybug for **months** and today where ever she looks, she’ll see the object of her hatred.

• In Puppeteer 2 (S3) Adrien once again assures is that he has only known Marinette and his other classmates for a few months which contradicts the popular belief that it has been years in the Miraculous world. He tells Marinette the following: Forgive me. Even after all these **months** with you guys I am still not used to being a good friend

• In “Feast” (S3) Alya says that the sentimonster in Alim Kubdel’s museum was the the last trace of a miraculous up to a few months prior. After viewing the mysterious Tibetan statue, Alix Kubdel says, “So.. this statue would be the last known trace of a miraculous.” Alya then replies with: “Until Ladybug & Cat Noir showed up a few **months** ago to fight Hawk Moth, yeah!”

• In the S3 episode “Felix” it is mentioned that it has been one year since Emilie Agreste fell into a coma. Gabriel Agreste did not become Hawkmoth until a while after her disappearance. We can assume this by how in “Origins- Part 1” Adrien says his father has not been the same for a while. It can also be said that Adrien would be more emotional about it if Emiline’s disappearance was a very new event. Adrien also seems to have become accustomed to Gabriel’s distant behavior which was a result Emiline’s disappearance.

• In S4 episode “Queen Banana”, reporter Clara Contaro states “He’s overseeing this group of students who are volunteering their own vacation time to produce a real life movie.” She is referring to their spring break and the episodes surrounding it possibly take place during their break as well. In France, spring break tends to be around the end of April. With this we can see the relative time span in how all the events from S1 to early S4 have been covering all the events that have happened from early September(the start of the French school year) to mid April.

• In S4 episode “Dearest Family,” Tom (Marinette’s father) tells Gina “Mom, Marinette’s last birthday was a few months ago. You were there.” This is a reference to S2 episode Befana which further establishes Marinette’s age as being 14.

Notes: The only episodes that don’t follow the approximated timeline are “Dark Cupid” and “Santa Claws”, but they can be rearranged as they don’t affect the plot much like most of the episodes in the earlier seasons. It is also important to keep in mind that Miraculous Ladybug was only meant to have three seasons in total. This means that they originally planned on having 3 seasons take place over the course of one school year (and have the two main love interests be together by then)as opposed to the current 4. However, do note that number has of expected seasons gone up because of the fans interest in the show and now we are expecting at least seven seasons in the Miraculous franchise.