Interactive tool

Monitor Arm Fit Checker

Check monitor size, weight, VESA pattern, count, mount type, and desk thickness against common arm classes with clear fit results.

Enter your monitor details and press Check fit. Results update the URL so you can share or bookmark them.

Monitor arm classes & VESA reference

Capacity, clamp range, VESA support, and panel ceilings for the four common monitor-arm tiers, derived from published Ergotron LX/HX, Fully Jarvis/Cooper, Herman Miller Flo, and Humanscale M2.1 spec sheets (2026).

Weight ratings are per arm. 'clamp_max_mm' is the published maximum desk thickness the bundled C-clamp accepts; thicker desks need the grommet-mount option. VESA values are the patterns the bundled plate drills to.

Single, light-duty

Jarvis Single Monitor Arm, Fully Cooper

Panel size: Up to 32 in
Weight range: 5-19.8 lb
Clamp range: 10-50 mm
VESA support: 75x75, 100x100 mm
Monitor count: single
Panel support: Ultrawide: No; curved: Yes

Gas-spring arms tuned for 24-27" mainstream panels. The 19.8 lb ceiling is the single most common reason a heavier 27"+ monitor sags.

Single, standard-duty

Ergotron LX, Humanscale M2.1, Herman Miller Flo

Panel size: Up to 34 in
Weight range: 4.4-25 lb
Clamp range: 10-60 mm
VESA support: 75x75, 100x100 mm
Monitor count: single
Panel support: Ultrawide: Yes; curved: Yes

The benchmark single-arm tier. Constant-force / counterbalance lift holds the full 4-25 lb range. Handles 34" ultrawides up to 25 lb.

Dual, standard-duty

Ergotron LX Dual, Fully Jarvis Dual

Panel size: Up to 27 in
Weight range: 7-20 lb
Clamp range: 10-60 mm
VESA support: 75x75, 100x100 mm
Monitor count: dual
Panel support: Ultrawide: No; curved: Yes

Two arms on one base, rated per-arm. Side-by-side dual works to ~27" each; two 32" panels exceed most desk-edge clamp leverage.

Heavy-duty / ultrawide

Ergotron HX, Ergotron HX Heavy-Duty

Panel size: Up to 49 in
Weight range: 11-42 lb
Clamp range: 10-90 mm
VESA support: 100x100, 200x100 mm
Monitor count: single
Panel support: Ultrawide: Yes; curved: Yes

Required for 38-49" superultrawide and heavy curved panels. Bundled plate drills 100x100 and 200x100; below 11 lb the arm is over-sprung and drifts up.

Triple / multi-mount

Ergotron LX Triple, freestanding multi-arm poles

Panel size: Up to 27 in
Weight range: 6-20 lb
Clamp range: 10-60 mm
VESA support: 75x75, 100x100 mm
Monitor count: triple
Panel support: Ultrawide: No; curved: Yes

Three arms demand a pole/desk-stand base, not a single C-clamp. Per-arm rating still applies; total moment usually caps practical panels at 24-27".

Methodology & data

Rule checks compare your inputs against published manufacturer spec ranges for the four common arm tiers (Ergotron LX/HX, Fully Jarvis/Cooper, Herman Miller Flo, Humanscale M2.1). Weight is normalised to pounds (1 kg = 2.20462 lb).

VESA, clamp-depth and panel-size checks are hard pass/fail. A weight within 90% of a tier's maximum is flagged CAUTION because gas-spring tension calibration drifts near the ceiling. Curved and ultrawide panels add a moment-arm caution unless the tier is rated for them.

This is a planning aid, not a substitute for the manufacturer's own load chart for your exact model.