I am in trouble with API marking :(

The new issue, how can I show the pipe length in marking?

Should I measure each pipe and add the result at the end of marking as meter, or
just adding "Range 1" at the end of marking is enough?

Marking / length normally mentioned by the Mill at the time of mill roll. However it all depends upon customer. Some people OK with Range 1, Range 2 or Range 3 description or some need exact length of tally of these joints. Like our customer issue purchase order on inch basis and we have to measure each and every pipe according to inches. Following is as per API5CT requirement
8.6 Length
Casing, tubing and pup joints shall be furnished in lengths conforming to Table C.27 or Table E.27. The length of
API couplings shall be as specified in Tables C.32 to C.35 or Tables E.32 to E.35 as applicable. The length of
coupling stock, coupling material and accessory material shall be as specified on the purchase agreement or, in
the case of coupling material and accessory material, the length shall be specified in the manufacturer's internal
requirements. The length of each finished product shall be determined for conformance to length requirements.
Length determination shall be in metres and hundredths of a metre (feet and tenths of a foot).
The accuracy of length-measuring devices for lengths of product less than 30 m (100 ft) shall be ± 0,03 m
(± 0.1 ft).