You hold the test under the light, turn it sideways, take a photo. There is something there - but is it real? This is one of the most common two-week-wait anxieties. The difference between an indent line and a true positive is learnable, and understanding it takes much of the confusion away.
Types of Lines You Might See
| Line Type | Colour | When Visible | What It Means |
|---|---|---|---|
| True positive | Pink or blue (matches control) | Within result window (5-10 min) | HCG detected - pregnant |
| Faint positive | Very light pink/blue | Within result window | Low but present HCG - likely early positive |
| Evaporation line | Grey or colourless | After result window (10+ min) | Evaporation of urine - not a positive |
| Indent line | Colourless indent in plastic | Any time | Manufacturing groove - not a positive |
How to Tell the Difference
- Read the test within the time window stated on the box (usually 3-10 minutes) - anything that appears after this is likely an evap line
- Look for colour - a true positive has colour (even if faint). An indent line has no colour at all
- Photograph it in natural light and enhance the image - a coloured faint line shows up; an indent remains colourless
- Retest with first morning urine - HCG doubles every 48-72 hours, so a true positive should be darker or the same
- Try a different brand - some brands are more prone to indent lines than others
The best rule
If you are unsure whether you see colour, test again in 48 hours with your first morning urine. If it is a true positive, it will be darker. If it was an indent, the result will be clearly negative.
Are Faint Positives Real
Yes. Any line with colour, no matter how faint, indicates HCG is present and you are pregnant. Most home tests detect HCG from about 25 mIU/mL. The sensitivity and your HCG level on test day determine how faint or dark the line appears. Very early tests (before your expected period) will naturally be fainter.