Toy Choking Hazard Size Checker
Check if a toy or part is a choking hazard under ASTM F963 and EN 71.
Enter dimensions to see if it fits the small parts test cylinder for under-3 labeling.
Why the small parts cylinder exists
The “no-choke” test cylinder used in ASTM F963 (US) and EN 71 (EU) is designed to approximate the size of a young child’s fully expanded throat. If an object fits entirely inside the cylinder, it can lodge in a child’s airway. The cylinder was developed in the 1970s by the US Consumer Product Safety Commission after a sharp rise in choking-related infant deaths from small toy parts.
The CPSC’s small parts regulation (16 CFR 1501) was the first major US toy-safety regulation specifically focused on choking. It’s been incorporated into ASTM F963 and is now the de facto global standard, with EN 71 closely matching.
The test cylinder dimensions
- Diameter: 31.75 mm (1.25 inches)
- Depth: 57.15 mm (2.25 inches)
- Angled at 45 degrees to catch elongated objects (a long thin object can rotate as it falls in)
An object is classified as a “small part” — and therefore a choking hazard for under-3 — if any portion of it fits entirely within the cylinder, even when compressed. This applies to soft toys, foam, plush that can be squished, and articulated parts that can rotate to fit.
The rule in plain language
A toy part is a small part (choking hazard) if all three are true:
- Width/thickness ≤ 31.75 mm (so it fits the cylinder diameter)
- Length ≤ 57.15 mm (so it fits the cylinder depth)
- Not permanently attached to a larger non-removable part
A small marble (12 mm diameter, fits in cylinder) is a small part. A doll’s plastic hand attached to a 30 cm doll body is not a small part — even though the hand alone fits in the cylinder — because it’s permanently attached. But if the hand can be pulled off with normal force, the hand becomes a small part.
Tested by the “tension test”
The cylinder is only the size test. There’s also a separation test: any part must withstand a 15 lbf (67 N) pull force for 10 seconds without separating. If a part can be pulled off and fits in the cylinder, the toy fails.
The implications:
- Glued-on eyes, hair, or accessories must survive the 15 lbf pull
- Snap-on parts must be tight enough not to pop off under normal play force
- Velcro and weak adhesives often fail this test
- Sewn-on parts (with secure stitching) typically pass
Balls and the small ball rule (separate stricter test)
Spherical objects have their own classification because they roll easily into a child’s airway:
| Object | Limit |
|---|---|
| Ball intended for children under 3 | Diameter ≥ 44.5 mm (1.75 in) |
| Small ball for older children | Warning label required if diameter < 44.5 mm |
| Marble | Always considered a small ball |
A ball that’s 44 mm diameter is too small for use with children under 3 — even though it doesn’t quite fit in the small parts cylinder. The 44.5 mm threshold exists because spheres can compress slightly in the throat.
Age labeling — the practical compliance
If your toy contains any small parts (per the rules above), it must be labeled for ages 3 and up. The required warning label:
WARNING: CHOKING HAZARD — Small parts. Not for children under 3 years.
The label must be:
- Conspicuous on the packaging
- Visible at point of sale (not hidden inside)
- In English (and Spanish in some retailers)
- Permanent on the toy itself if sold without packaging
Failure to label is a CPSC violation, with fines up to $115,000 per violation and possibly per individual unit sold.
What’s exempt from the small parts rule
Certain categories are explicitly exempt or have specific allowances:
- Books with cardboard pages — pages don’t count as small parts
- Modeling clay and dough — naturally large lumps
- Toy musical instruments with hard-to-remove components
- Crayons and chalk — even though they fit the cylinder
- Latex balloons (uninflated) — but with specific balloon warning required
- Toys with batteries in a secured compartment — battery compartment must require tools to open
Common small-parts failures I’ve seen
When safety testing labs evaluate toys, the typical failures:
| Component | Why it fails |
|---|---|
| Doll/plush eyes | Plastic safety eyes can pull through fabric backing |
| Pom-poms and tassels | Fall off easily with hand pulling |
| Stick-on accessories (foam stickers, googly eyes) | Adhesive fails over time |
| Buttons sewn on with single-loop thread | Pull off with 5 lbf, not 15 |
| Wheel pins on toy cars | Snap or pull out |
| Decorative ribbons | Untie or break |
| Soft squishies that can compress and fit | Often surprise sellers; squishability matters |
| Magnets | If small AND magnetic, separately regulated under stricter rules |
| Removable hats/clothing on dolls | Pieces qualify as small parts |
The 100-screen safety review
Before sending a toy for commercial production, run this mental review:
- Pick up the toy and try to pull off every component with reasonable force
- Drop the toy on a hard floor from 3 feet — see what comes loose
- Wash the toy or expose it to humidity for 24 hours — does adhesive weaken?
- Bend, twist, and compress any soft parts — do they hide a small part underneath?
- Apply 15 lbf force to every glued/sewn/snapped component for 10 seconds
- Measure every potential small part against a 31.75 × 57.15 mm cylinder
If you don’t have a cylinder, a film canister is approximately the right size for screening (33 mm × 57 mm — close enough for rough check). Order a real test cylinder for $30-$50 if you’re producing toys commercially.
Magnets — a separate dangerous category
Small high-powered magnets (rare earth, NdFeB) have their own much stricter regulations after multiple deaths from children swallowing multiple magnets that then pinched intestinal walls. The regulations:
- Magnets accessible to children under 14 are restricted by flux index
- Sets of small magnetic balls (Buckyballs and similar) are effectively banned for children’s toys
- Magnetic toy components must either be too large to swallow OR too weak to attract through tissue
If your toy contains rare-earth magnets, consult the CPSC magnet regulations specifically — the small-parts rule alone doesn’t cover the additional magnetic hazard.
The commercial reality
For a handmade Etsy seller making 100 toys/year, formal lab testing is overkill but the safety rules still apply. For commercial production (1,000+ units), expect:
- Third-party CPSC testing at a registered lab — $500-$2,000 per toy
- CPSC product registration before sale
- Tracking labels on each unit (required for children’s products)
- Children’s Product Certificate (CPC) — your own attestation of compliance
The legal liability for a child injured by a non-compliant toy is severe. Even non-commercial gift-giving can result in lawsuits if a child is hurt.
Bottom line
If any part of your toy fits in a 31.75 × 57.15 mm cylinder and isn’t permanently attached, the toy is for ages 3+ only, and the warning label is required. For children under 3, every component must be either too large for the cylinder or permanently attached with 15+ lbf pull strength. When in doubt, design conservatively — the safety margin is cheap; injury liability is not.