Here's a guideline for how I grade records. Not all records will fit "exactly" into a certain grade, and one should assume a certain amount of tolerances within each grade.
Assume grading to be "visual" unless noted. I grade under a powerful 100 watt bulb.
+/-: I use pluses and minuses to help indicate more or less issues in a certain grade.
Grades for vinyl :
M : new, un-played, perfect.
NM: like new but possibly carefully played a limited amount of times. Should play near perfect with almost no noise or imperfections. May show very faint imperfections from paper scuffs or tiny needle marks.
EX : as above with a few light needle marks, or a few light surface scuffs, and/or lightly audible marks. a very nice used record.
VG : still showing gloss but lots of small scratches and scuffs or some groove wear. A used/played record that should still play through without skips, but will have light surface noise throughout, pops, ticks, and maybe some distortion/sibilance. I do not consider VG to be a complete junk grade but it is not audiophile quality by any means.
VG- to G : any record in less than VG condition that I feel is still worth offering due to rarity, but it may have play problems.
Grades for covers:
M : perfect. no wear, square flat corners, solid seams, spine etc., Usually sealed.
NM : overall appearance of front and back near perfect but may have a very small problem such as a small corner ding/couple tiny spine chips, but nothing noticeable without close inspection.
EX : as above, nice "un-handled" feel, but may have more spine wear, a bent corner or two, very light ring wear, but rarely any splits or tears.
VG: still have a nice overall appearance, but may have the following defects: seam splits, spine splits, small tears, ring wear, writing, small stains, etc. in various (not severe) degrees.
VG- to G : getting ugly, but still worth offering due to rarity or LP contained within.
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