Estimate, appraise, evaluate, value, rate, assess, assay are comparable when meaning to judge a thing with respect to its worth.
Estimate usually implies a personal and sometimes a reasoned judgment which, whether considered or casual, is by the nature of the case neither thoroughly objective nor definitive.
Appraise implies the intent to fix definitely and in the capacity of an expert the monetary worth of the thing in question usually in terms of the price it ought to bring in the market if sold, or in case of its loss (as by fire or theft) the monetary compensation due its owner from an insuring company. In extended use appraise, in contrast to estimate, implies an intent to give a final, an accurate, or an expert judgment of a thing’s worth; estimate, therefore, is often preferred by persons speaking of their own judgments because appraise seems presumptuous or pretentious.
The participial adjective appraising is often used to qualify eye, glance, look; it then suggests close, critical inspection or scrutiny.
Evaluate, like appraise, suggests an intent to arrive at a mathematically correct judgment; it seldom suggests, however, an attempt to determine a thing’s monetary worth, but rather to find its equivalent in other and more familiar terms.
Value (see also APPRECIATE 2 ) comes very close to appraise in that it also implies an intent to determine or fix the market price but differs from appraise in that it carries no implication of an authoritative or expert judgment and must depend on the context to make that point if it is essential.
In extended use and in reference to things not marketable, value is often found with a negative or with a restrictive word such as only.
Rate often adds to estimate the implication of fixing in a scale of values.
Assess implies valuing for the sake of determining the tax to be levied; in extended use it implies a determining of the exact value or extent of a thing prior to judging it or to using it as the ground for a decision.
Assay basically implies chemical analysis for the sake of determining a substance’s (usually a metal’s) quality, quantity, or value; in extended use it implies a critical analysis for the sake of measuring, weighing, and appraising.