A grade is a promise about a used phone. If two technicians can reach different grades from the same device, the promise is not a standard. The rules have to be written before the label is printed.
Good grading starts with function and ends with evidence.
Function first
A phone with a failed camera should not reach grade A because the body is clean. Test the display, touch, cameras, speaker, microphone, connectivity, charging, battery, sensors and physical inputs before considering appearance.
Keep skipped tests separate from failures. A device with an untested port is a different risk from one with a broken port.
Cosmetic bands
Cosmetic grading needs structure. Define regions (screen, back, frame, camera lens), mark types (scratch, dent, crack, discoloration) and severity levels. Require a photo for anything above light wear.
A simple three-band scale works for many channels:
- A: no visible marks or one faint mark, screen perfect.
- B: light scratches or minor frame wear, no cracks.
- C: visible scratches, dents or screen wear, fully functional.
The exact thresholds are a business decision. The important part is that they are written down and applied consistently.
Battery health
Battery health is a commercial input, not a cosmetic one. A device at 78 percent health may still be grade B cosmetically but needs a battery replacement before resale.
Set a cutoff by channel. A consumer buyer expects a higher minimum than a trade buyer who will refurbish the device again.
Display and parts
On Android, a display authenticity check can reveal a replacement panel. Record the result and factor it into the grade or the price. On iOS, use the parts and service history the platform exposes.
A replaced screen is not automatically a lower grade, but it changes the warranty and the buyer’s expectation. State it in the report.
Channel-specific grades
The same phone can be grade A for a trade buyer and grade B for a consumer. That is acceptable if the channel is recorded.
Map the internal grade to each marketplace’s condition taxonomy. Keep the mapping in configuration, because marketplaces change categories more often than refurbishers change standards.
Evidence
Every grade should link to the test result, the cosmetic photos and the rule version. When a buyer disputes a scratch, the evidence answers the question without an argument.
A grade without evidence is an opinion. An opinion is hard to defend at scale.
A grade card and dispute handling
A grade card should show the overall grade, the component scores, the cosmetic band and the findings that changed the result. A buyer should be able to see why a phone is B rather than A.
Attach the test readings and the cosmetic photos. The card is a summary; the evidence sits behind it.
Record the rule version and the date. When a standard changes, old grades should remain explainable under the version that produced them.
Handle disputes with the evidence, not a new opinion. If the buyer and the seller disagree, compare the photos and the test readings from the same run. A second inspection can confirm the finding, but it should not overwrite the original record.
Mapping to marketplaces
Each marketplace has its own condition labels. Build a mapping table from your internal grade to the external label, and keep the evidence behind the internal grade.
Do not let the marketplace label replace the internal grade. The external label is a listing field; the internal grade is the record you use for warranty and disputes.
Review the mapping when a marketplace changes its categories. A stale mapping can make a grade B phone appear as grade A on one channel.
FAQ
What is the difference between grade A and grade B?
Grade A is near-new cosmetic condition with no functional failures. Grade B has light wear but remains fully functional. Define the exact thresholds in writing.
Does a replaced screen lower the grade?
It can, depending on the channel and the warranty. Record the replacement and state it in the report rather than hiding it in the grade.
Can one phone have two grades?
Yes, for different channels. Keep the channel and the rule version on the record so the difference is explainable.
For the product side, see device grading software, mobile QC software and device buyback software.
