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#4 of 11

Yumbox Original Leakproof Bento Lunch Box

Key Specs

Tray Material

Outer Shell Material

Seal Material

Compartments

Yumbox

Yumbox Original Leakproof Bento Lunch Box

#4 of 11 lunch boxs tested

No sponsored placements·By Renée Torres

6.7R3 Score / 10

There are better options - here's why.

No sponsored placements· By Renée Torres

Safety

The bottom line

What the product listing won't tell you

Know before you buy

The Yumbox Original's single-lid leakproofing and single-latch ease of opening are genuinely the best in class for ages 3–7, but you're getting a Tritan plastic food-contact tray — not stainless steel — with no PFAS-free claim, a compartment capacity that scores low for older kids, and a shell that needs hand washing every day.

Buy it if

Usability

Efficacy

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$32.99

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Your child is ages 3–7 and needs to open their lunch box independently — the single latch is the easiest in the category.

You need reliable all-compartment leakproofing for wet foods like yogurt, fruit, and sauces.

Portion control matters — the 5+dip-well layout keeps every food group separated and visible.

You want replacement parts to extend the box's life without buying a new one each year.

Budget is a consideration — at $32.99, it's strong value for what it delivers.

Skip if

You want a plastic-free food-contact tray — the Yumbox Presto or Pret have stainless steel trays.
You need the entire box (not just the tray) to be dishwasher safe — the shell requires daily hand washing.
Your child is older or a bigger eater — the 2.5–4 cup capacity may not be enough.
Your child packs tomato sauce, curry, or berries frequently — expect tray staining within 6–12 months.

What's inside

Specs the product listing doesn't explain

Safety & Materials

What your food and family come into contact with every use

Tray Material Outer Shell Material Seal Material Dishwasher Safe Certifications

Usability

Ease of use, maintenance, and longevity

Compartments Empty Weight Dimensions Leakproof

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How we scored it

6 criteria - open any layer to see exactly what we found

Safety

Efficacy

Usability

Food Contact Material SafetyCritical

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Criteria

Safety research

Safety standards and ingredients related to Yumbox Original Leakproof Bento Lunch Box

Microplastics from Heated Plasticsingredients

Microscopic plastic particles smaller than 5mm (microplastics) and smaller than 1 micrometer (nanoplastics) that shed from plastic components when repeatedly heated. Recent studies show heated plastics release millions of micro- and nanoplastic particles per gram. These particles have been found in human blood, placenta, and breast milk, and can carry other chemicals like phthalates and BPA as they leach into food and air.

Melamineingredients

An organic compound used to make hard, heat-resistant plastic (melamine resin). Found in cheap air fryer accessories, dishes, and utensils. Leaches formaldehyde when heated above 160 degrees F (70 degrees C). Not safe for high-heat cooking. Associated with kidney damage and the 2008 Chinese milk contamination scandal.

Phthalatesingredients

A group of plasticizer chemicals used to make plastics flexible and durable. Found in PVC, vinyl, food packaging, personal care products, and kitchen appliance components. Phthalates are endocrine disruptors that affect testosterone and thyroid hormones, with strong evidence linking them to reproductive harm, particularly in developing boys.

Every term is independently researched and sourced.

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