Clotting factors are procoagulant substances contained in plasma. They were officially named in Roman numerals in the order in which they were discovered.

 

Clotting factor number: I 

Clotting factor name: Fibrinogen

Function: Clot formation

 

Clotting factor number: II 

Clotting factor name: Prothrombin

Function: Activation of I, V, VII, VIII, XI, XIII, protein C, platelets

 

Clotting factor number: III 

Clotting factor name: Tissue factor（TF）

Function: Co factor of VIIa

 

Clotting factor number: IV 

Clotting factor name: Calcium

Function: Facilitates coagulation factor binding to phospholipids

 

Clotting factor number: V 

Clotting factor name: Proacclerin, labile factor

Function: Co-factor of X-prothrombinase complex

 

Clotting factor number: VI

Clotting factor name: Unassigned

 Function: /

 

Clotting factor number: VII

Clotting factor name: Stable factor, proconvertin

Function: Activates factors IX, X

 

Clotting factor number: VIII

Clotting factor name: Antihaemophilic factor A

Function: Co-factor of IX-tenase complex

 

Clotting factor number: IX 

Clotting factor name: Antihaemophilic factor B or Christmas factor 

Function: Activates X: Forms tenase complex with factor VIII

 

Clotting factor number: X

Clotting factor name: Stuart-Prower factor

Function: Prothrombinase complex with factor V: Activates factor II

 

Clotting factor number: XI

Clotting factor name: Plasma thromboplastin antecedent 

Function: Activates factor IX

 

Clotting factor number: XII 

Clotting factor name: Hageman factor 

Function: Activates factor XI, VII and prekallikrein

 

Clotting factor number: XIII

Clotting factor name: Fibrin-stabilising factor

Function: Crosslinks fibrin

 

Clotting factor number: XIV

Clotting factor name: Prekallikerin (F Fletcher) 

Function: Serine protease zymogen

 

Clotting factor number: XV

Clotting factor name: High molecular weight kininogen- (F Fitzgerald)

Function: Co factor

 

Clotting factor number: XVI

Clotting factor name: Von Willebrand factor

Function: Binds to VIII, mediates platelet adhesion

 

Clotting factor number: XVII

Clotting factor name: Antithrombin III 

Function: Inhibits IIa, Xa, and other proteases

 

Clotting factor number: XVIII 

Clotting factor name: Heparin cofactor II 

Function: Inhibits IIa

 

Clotting factor number: XIX

Clotting factor name: Protein C 

Function: Inactivates Va and VIIIa

 

Clotting factor number: XX

Clotting factor name: Protein S

Function: Cofactor for activated protein C