Flag of Slovakia — construction sheet
Own work. Geometry and dimensions are mostly based on the legal description and appendices in Law no. 63/1993 Act of the National Council of the Slovak Republic on state symbols of the Slovak Republic and their use.

The national flag of the Slovak Republic (hereinafter referred to as the "national flag") consists of three longitudinal stripes - white, blue and red, of the same width, arranged one below the other. The national coat of arms is placed on the front half of the sheet of the national flag. 5 ) The national emblem on the national flag is equidistant from the top, front and bottom edges of the national flag and its height is equal to half the height of the national flag. At the junction of the shield with a color other than white, there is a white border, one-hundredth of the length of the national flag. No contour line is used in the national emblem on the national flag. The aspect ratio of the national flag is 2:3.— English translation of an extract from Law no. 63/1993 section 7.1

The Law specifies a height for the shield but not a width.  Measurements from the flag in the appendices of Law 63/1993 give a value about 12⁄45 the length of the flag which matches what is shown at Flags of the World (FOTW).
The shape and characteristics of the shield elements on this construction are based on a combination of:

The blurry diagrams in the appendices of Law 63/1993
The government SVG file available for download at vlada.gov.sk
Note that the government SVG file suffers from several issues: the ratio is not exactly 2:3; the border around the emblem is too fat, the emblem is in the wrong place, etc.
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