196 feet 3 inches from tip of bow to bridge front.
If you want to check it, go to the "home" page for this site. Find "plans" at the top. Click on plans and open "profile"....zoom to the bottom of ship profile and you will see the numbered frames and the distances between them. Then count frame spaces from the very first perpendicular. you wil need a ruler to measure the first bit. Use the frame spaces as a scale.
One actually does not need a ruler to measure the first bit. The distance between frame 155 (shown but not labelled on the deckplans here) and the forward perpendicular can be found by subtracting all the known lengths from the LBP (850’0”), using the numbering and frame spacing to perform the subtraction piecewise. From frame 155 to the forward perpendicular, the distance is 3’8”.
From forward perpendicular to bowsprit, 2’6” (this difference comes from the fact that the Board of Trade measured LBP from the bowsprit, giving 852’6”, where the builders measured from forward perpendicular, giving 850’0”). The extra expanse beyond frame 155 is therefore 6’2”.
From frame 80 (the frame aligned with the bridge front) to frame 95, 45’0”. From frame 95 to frame 107, 33’0”. From frame 107 to 119, 30’0”. From frame 119 to frame 134, 33’9”. From frame 134 to frame 155, 42’0”. From frame 155 to bowsprit, 6’2”.
From bridge to bowsprit the full distance was 189’11”.
Actually, I measured to Frame 82... front of C deck.
However, the quickest way to arrive at the desired length is simply to subtract the distance between the mid-ship mark and Frame 80 from half the overall (Registered) length.
Half Overall length.... = 441 feet - 4.5 inches.
Midship to Frame 80. = 238 feet - 6.0 inches.
Top of Stem to Fr.80..= 202 feet - 10.5 inches
Hang on a second, wouldn’t the mid-ship mark signify the midway point between perpendiculars, not the midway point overall? Try checking to see if the distance from aft perpendicular to frame 1 aft is almost the same as the distance from forward perpendicular to frame 1 fore.
The mid-ship point shown on the plan is the midpoint on the freeboard length. i.e. it is the length of the freeboard deck which in the case of Titanic seems to have been deck "D"
If so, the distance between the fore part of the stem bar at "D" deck and the forward end of the stem bar on the forecastle deck 2 feet, therefore, the distance between the midship point and the overall length perpendicular at the bow is 425 + 2 = 427 feet
To find the distance between Frame 80 at the bridge and the top of the stem bar, you should, therefore, subtract 238 feet 6 inches from 427 feet. This gives a distance from the bow to the bridge of 188 feet 6 inches.