Both are Levi's lines. 511 Slim: Runs Narrow — True to waist; size up if muscular thighs or between. 501 Original Fit: True to Size — True to waist; check shrink-to-fit vs pre-washed.
Levi’s 511 Slim is true to tagged waist with a slim thigh/knee. Stay at your measured waist unless you have muscular thighs or are between sizes — then size up one. It is not a skinny 721; it is also not a 501 straight.
Levi’s 501 Original is true to tagged waist on pre-washed pairs. Shrink-to-Fit is a different product: size up in waist and inseam before the first hot soak. Stretch 501s follow the same waist number with more give. Do not mix STF advice into a pre-washed 501.
Nominal sizes often match; compression and fabric change how the size feels. Between sizes, Align lean larger for fabric longevity; Wunder Train lean TTS (or smaller only for extra hold).
(paid link)
| 511 Slim | 501 Original Fit | |
|---|---|---|
| Verdict | Runs Narrow | True to Size |
| Advice | True to waist; size up if muscular thighs or between | True to waist; check shrink-to-fit vs pre-washed |
| Fabric / fit notes | Slim through thigh/knee | Straight classic; STF shrinks — pre-wash differs |
| Stretch | Often low–medium stretch | Varies by fabric (rigid / stretch) |
| Rise | mid | mid |
| Confidence | high | high |
Crawlable starting point when both lines use the same numeric system. Adjust for compression preference.
| If 511 Slim size | Try 501 Original Fit | Note |
|---|---|---|
| 0 | 0 | same numeric ladder |
| 2 | 2 | same numeric ladder |
| 4 | 4 | same numeric ladder |
| 6 | 6 | same numeric ladder |
| 8 | 8 | same numeric ladder |
| 10 | 10 | same numeric ladder |
| 12 | 12 | same numeric ladder |
| 14 | 14 | same numeric ladder |
Full 511 Slim guide · Full 501 Original Fit guide · Reverse compare · All Levi's lines
Check prices: 511 Slim 501 Original Fit (paid link)