Shower Seal Fit Fit by the numbers

Measured fit, not guesswork

Find the right shower door seal by glass thickness and gap.

Two measurements decide whether a replacement seal fits: how thick your glass is, and how big the gap the seal must close. Enter them below — the finder scores our reviewed catalog of sweeps, drip rails, side seals, magnetic pairs and jambs, and explains every match.

  • 5 glass sizes
  • 7 gap sizes
  • 8 door types
  • 11 seal families
  • 100-point fit scoring
Bright modern bathroom with a frameless glass shower enclosure and dark slate feature wall

3/8″ · 9.5 mmthe US standard glass on frameless hinged doors

I don't know my glass thickness

Open the door and look at the exposed edge — that face's width is the thickness. Then:

  • Best: a caliper on the bare edge. 6.35 mm = 1/4″, 7.9 mm = 5/16″, 9.5 mm = 3/8″, 12.7 mm = 1/2″.
  • Tape measure: hold it flat across the edge, eyes level with the glass. Distinguishing 3/8″ from 1/2″ needs a straight-on view.
  • Paper trace: press a card against each face and mark both sides on paper, then measure between the marks.
  • Rules of thumb: framed sliding doors are usually 3/16″–1/4″; semi-frameless 1/4″–5/16″; frameless hinged 3/8″; heavy premium frameless 1/2″.

Full walkthrough: How to measure shower door glass thickness.

How this site works

  1. Measure two numbers. Glass thickness at the bare edge, and the gap (bottom, side, or door-to-wall) with the door closed. The measuring guides take five minutes.
  2. Get scored matches. Every product in the catalog carries manufacturer size ranges with a review date. Your inputs are checked against those ranges — 100 for an exact fit, 80 when trimming is expected, 60 near the edge of a range, 30 for risky combinations.
  3. Verify on the live listing. We show no prices or stock — both change too fast to republish honestly. Confirm the stated size range on the retailer's live listing before you buy.

Start from what you know

Or start from your door type

The construction decides the seal family before any measurement does — sliders need offset fins that clear the track, bifolds need a strip that flexes with the fold, neo-angles need 135° profiles.

Sliding & bypass doors 1/4″ · 5/16″ · 3/8″ glass Bathtub doors 3/16″ · 1/4″ · 3/8″ glass Pivot doors 3/16″ · 1/4″ · 3/8″ · 1/2″ glass Bifold doors 3/16″ · 1/4″ glass Neo-angle doors 1/4″ · 3/8″ glass Curved & round doors 3/16″ · 1/4″ · 5/16″ glass Steam shower doors 3/8″ · 1/2″ glass Corner doors (90°) 1/4″ · 3/8″ · 1/2″ glass

The two measurements, visualized

US shower glass thickness classesRuler showing the five common shower door glass thicknesses from three sixteenths to one half inch with millimeter equivalents.3/16″4.8 mmframed1/4″6.35 mmframed · light FL5/16″8 mmsemi-frameless3/8″9.5 mmframeless std1/2″12.7 mmpremium
Every press-on seal is sized to one of these classes — the channel must match the measured edge exactly. Metric twins (6, 8, 10, 12 mm) fit the same seals in flexible PVC.
Wipe height by bottom gapChart matching each measured bottom gap to the flexible wipe height that seals it: the wipe should be about an eighth to a quarter inch taller than the gap.MEASURED GAPWIPE THAT COVERS IT1/8″3.2 mm1/4″ wipelow-profile — avoids drag1/4″6.4 mm1/2″ wipethe frameless standard3/8″9.5 mm1/2–3/4″ wipego 3/4″ if the gap varies1/2″12.7 mm3/4″ wipecombo with drip rail is common5/8″15.9 mm1″ wipelisted as “extra tall”3/4″19.1 mm1″ wipecheck stated wipe height1″25.4 mmfix geometrythreshold or hinge adjustment first
Rule of thumb: wipe height ≈ gap + 1/8–1/4″. A wipe equal to the gap hovers and never seals; one 1/2″ taller drags.

Beyond seals: parts & care

Door parts that wear out

Sliding doors fail at the hardware long before the glass: rollers, the bottom guide, handles, hinges and the track. Each page shows the one or two measurements that decide the replacement.

Popular tools & guides