(according to the Russian Retriever Club)

AGE Month	WEIGHT Kg	HEIGHT WITHERS см	CHEST см	HEADS GIRTH см	FACE SIZE см	GABLE SIZE см	METACARPUS SIZE см
1	3,4-3,8	23-23,5	37-38	27-28	17	3,5-4	9
2	7-8	30-32,5	45-46	29-32,5	20,5-22	4,5-5,5	10,5-11
3	12-14	39,5-42	51-56	34-36	23-24	6-7	11,5-12
4	17-19	44-46	60-64	38-39	24-26	7-8	11,5-12
5	21-22	48-51	66-68	41-42	25-27	7,5-8,5	11,5-12,5
6	24-26	50-55	67-70	42-43	27-28	7,5-9	11,5-12,5
7	26-28	52-56	69-74	43-44	28-29	7,5-9	11,5-13
8	28-30	54-57	70-76	45-46	28-30	7,5-9	11,5-13
9	29-32	54-58	70-77	46-48	28-31	7,5-9,5	11,5-13,5
10	30-36	54-58	70-84	46-55	28-32	7,5-10	11,5-14
adult	30-38	54-61	70-86	46-56	28-32	7,5-10	11,5-14

Height in withers for males - 56-61 cm, for bitches - 51-56 cm
The given parameters are approximate. It is not necessary that your Golden retriever or Labrador has 26 kg in weight when he is 6 months. The "Correct" weight of a puppy is determined not only by its age, but also by growth which depends on genetic predisposition of a dog. Some dogs grow more quickly, others more slowly. The important thing is that a dog should be physically fit. To overfeed a puppy is very unhealthy. It will not entail his quick growth, but can lead to skeletogeny problems.

Except for that, Golden retrievers and Labradors are usually more fit and thin if they are "working" dogs, and fattened if they are show-dogs.
For correct measurement the dog should be put on a plane surface so that it stands firmly on all four foots. The legs should not be put forward or backward. The head should not be lowered or thrown back.

 

1 – head’s length; 2 - width of a head in cheekbones; 3 – muzzle’s length; 4 - height at withers; 5 - height at sacrum; 6 - slanting length of a trunk; 7 - width of a breast in front; 8 - length of a forward leg; 9 - depth of a breast; 10 - grasp of a breast; 11 - grasp of a metacarpus