The indicative future perfect tense in French is used to express actions that will happen and be completed in the future. It also has other applications, such as being used to express probability in the past, talking about historical events and for the subordinate clause in timed events where the subordinate clause happens after or before the main clause and that follows one of the following conjuctions: 
quand, 
lorsque, 
aussitôt que, 
une fois que, 
dès que or 
après que. Its English equivalents are as follows:
                        
                            - 
                                Future perfect tense
                                
                                The tense that is composed as will have plus the past participle of the verb.
                                
 
                                    例如 I will have gone to the shop.
                                 
- 
                                Probable/suppositive past tense
                                
                                The tense that is composed as must have plus the past participle of the verb.
                                
 
                                    例如 I must have gone to the shop.
                                 
- 
                                Historical past tense
                                
                                The tense that is composed with the '-ed' ending and when you're talking about a historical event.
                                
 
                                    例如 Louis XVII went to the shop.
                                 
- 
                                Resultant complementary subordinate clause
                                
                                The subordinate clause which happens before or after the main clause and that follows one of the following conjunctions: quand (when), lorsque (when), aussitôt que (as soon as), une fois que (once), dès que (as soon as) or après que (after).
                                
 
                                    例如 I will go to the shop, as soon as you leave.
                                 
                        Conjugate the verb 
avoir (to have) in the indicative simple future tense and use the 
past participle.
                        
                            
                            
                                
                                            
                                                | J' | aurai + PP | I | 
                                                
                                                    | Tu | auras + PP | you (s.) | 
                                                
                                                    | Il | aura + PP | he, she, it | 
                                                
                                                    | Nous | aurons + PP | we | 
                                                
                                                    | Vous | aurez + PP | you (p., pol.) | 
                                                
                                                    | Ils | auront + PP | they | 
                                
                            
 
                            
                            With some verbs you will need to conjugate the verb 
être (to be), instead of 
avoir (to have), in the indicative simple future tense and use the 
past participle. There are only a small handfull of these verbs, find all 
être verbs and more information 
here.
                            
                            
                            
                                
                                            
                                                | Je | serai + PP | I | 
                                            
                                                | Tu | seras + PP | you (s.) | 
                                            
                                                | Il | sera + PP | he, she, it | 
                                            
                                                | Nous | serons + PP | we | 
                                            
                                                | Vous | serez + PP | you (p., pol.) | 
                                            
                                                | Ils | seront + PP | they |