Skill Checks
Source Player Core pg. 397
Starfinder has a variety of skills for many different situations, from Athletics to Computers to Piloting. Each grants you a set of related actions that rely on you rolling a skill check. Each skill has a key attribute modifier, based on the scope of the skill in question. For instance, Athletics deals with feats of physical prowess, like swimming and jumping, so its key attribute modifier is Strength. Computers deals with the ability to work with computer systems and other technological equipment, so its key attribute modifier is Intelligence. The key attribute modifier for each skill is listed in Chapter 4: Skills. No matter which skill you're using, you calculate a check for it using the following formula.
Skill check result = d20 roll + the skill's key attribute modifier + proficiency bonus + other bonuses + penalties
You're unlikely to be trained in every skill. As normal, when using a skill in which you're untrained, your proficiency bonus is +0; otherwise, it equals your level plus 2 for trained, or higher once you become expert or better. The proficiency rank is specific to the skill you're using. Aid from another character or some other beneficial situation might grant you a circumstance bonus. A status bonus might come from a helpful spell or magical effect. Sometimes tools related to the skill grant you an item bonus to your skill checks. Conversely, unfavorable situations might give you a circumstance penalty to your skill check, while harmful spells, magic, or conditions might also impose a status penalty. Using shoddy or makeshift tools might cause you to take an item penalty. Sometimes a skill action can be an attack, and in these cases, the skill check might take a multiple attack penalty.
When an ability calls for you to use the DC for a specific skill, you can calculate it by adding 10 + your total modifier for that skill.
Skill check result = d20 roll + the skill's key attribute modifier + proficiency bonus + other bonuses + penalties
You're unlikely to be trained in every skill. As normal, when using a skill in which you're untrained, your proficiency bonus is +0; otherwise, it equals your level plus 2 for trained, or higher once you become expert or better. The proficiency rank is specific to the skill you're using. Aid from another character or some other beneficial situation might grant you a circumstance bonus. A status bonus might come from a helpful spell or magical effect. Sometimes tools related to the skill grant you an item bonus to your skill checks. Conversely, unfavorable situations might give you a circumstance penalty to your skill check, while harmful spells, magic, or conditions might also impose a status penalty. Using shoddy or makeshift tools might cause you to take an item penalty. Sometimes a skill action can be an attack, and in these cases, the skill check might take a multiple attack penalty.
When an ability calls for you to use the DC for a specific skill, you can calculate it by adding 10 + your total modifier for that skill.