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Short answer: Both hold about a pint (17 oz vs 16 oz) and are nearly the same size. Choose the Zojirushi SW-EAE50 for the lighter jar (11 oz vs 0.8 lb) and a published 147°F at 6 hours. Choose the Thermos Stainless King for its folding spoon, serving-bowl lid, and pressure-relief stopper.
How we compare: every spec in this article comes from official manufacturer specifications and manuals (starting with Zojirushi’s official product page and Thermos’s official product page), all listed under Sources below. We don’t run hands-on tests, and if a spec isn’t published, we say so. Last updated: October 2026.
I live in Japan. In Japan, a soup jar (“sūpu jā”) is a normal part of a packed lunch. These two are the pint-size jars most Americans end up choosing between.
I haven’t tested these side by side. Everything below comes from the manufacturers’ official product pages, linked at the end. If a spec isn’t published, I say so instead of guessing.
Recall note: In April 2026, Thermos and the U.S. Consumer Product Safety Commission (CPSC) recalled Stainless King 16 oz Food Jars (model SK3000) and 24 oz Food Jars (SK3020) manufactured before July 2023 whose stopper has no pressure relief in the center, along with all 40 oz Sportsman bottles (SK3010). The model number is printed on the bottom. If you own an affected jar, stop using it and request a free replacement stopper from Thermos. Thermos says the recall covers only SK3000 and SK3020 jars without a pressure-relief stopper, and its current 16 oz product page lists a pressure-relief stopper. Details: CPSC recall notice and Thermos recall page.
Quick Comparison Table
| Spec | Zojirushi SW-EAE50 | Thermos Stainless King 16 oz |
|---|---|---|
| Capacity | 17 oz / 0.5 L | 16 oz (475 mL) |
| Dimensions | 3-5/8 x 3-5/8 x 6 in (W x D x H) | 3.7 W x 3.7 D x 5.6 H in |
| Weight | 0 lb 11 oz (listed as 0.11 lbs.oz.) | 0.8 lb |
| Heat rating | 147°F after 6 hours* | Up to 9 hours hot |
| Cold rating | 50°F after 6 hours* | Up to 14 hours cold |
| Steel | 18/8 stainless, SlickSteel finish | 18/8 stainless |
| Opening | 2-1/2 in wide | Wide mouth (width not listed) |
| Included extras | Not listed | Folding spoon, serving-bowl lid |
| Lid | Tight-fitted lid with gasket | Pressure-relief stopper |
| Dishwasher | Not listed | Top rack only |
| Made in | Thailand | China |
*Zojirushi rates heat retention with 203°F (95°C) water in a 68°F (20°C) room, and cold retention with 40°F (4°C) water in the same room.
Key differences at a glance
- Heat rating: Zojirushi lists 147°F after 6 hours, while Thermos lists “up to 9 hours hot” without a temperature.
- Weight: The SW-EAE50 weighs 11 oz, about two ounces less than the Stainless King’s 0.8 lb.
- Accessories: The Thermos includes a folding spoon and a lid that doubles as a serving bowl, while the Zojirushi lists neither.
- Cleaning: Thermos says top-rack dishwasher safe, while Zojirushi’s page doesn’t say the SW-EAE50 is dishwasher safe.
- What stays the same: Both are double-wall vacuum-insulated 18/8 stainless jars about 3.6 to 3.7 inches wide.
The 4 Differences That Matter
1. How heat retention is rated
Zojirushi gives an end temperature: water that started at 203°F was still 147°F after 6 hours. Thermos gives a duration: “hot for up to 9 hours.” Thermos doesn’t say what temperature counts as hot, so the two numbers can’t be ranked against each other. If you want a number you can plan around, only Zojirushi gives you one.
2. Weight
The SW-EAE50 is listed at 11 oz; the Stainless King at 0.8 lb (about 13 oz). That’s about two ounces, which you’ll notice more in a kid’s backpack than in a commuter bag.
3. What’s in the box
Thermos includes a stainless folding spoon that stores in the lid, and the lid doubles as an insulated serving bowl. Zojirushi’s page doesn’t list a spoon. You eat straight from the 2-1/2-inch opening.
4. Cleaning
Thermos says top-rack dishwasher safe. Zojirushi’s page doesn’t say the SW-EAE50 is dishwasher safe, so I’d plan on hand-washing it.
What’s the same
Both are double-wall vacuum-insulated 18/8 stainless jars about 3-5/8 to 3.7 inches wide, sized for one lunch portion of soup, oatmeal, or chili.
Who Should Buy Which?
Choose the Zojirushi SW-EAE50 if you:
- Want the lighter jar
- Want a published 6-hour temperature figure
- Like the five color options
Choose the Thermos Stainless King 16 oz if you:
- Want a spoon and serving bowl built in
- Want top-rack dishwasher cleaning
- Want the pressure-relief stopper
Food Jars in Japan
In Japan, these are usually called “soup jars” (スープジャー), and they’re a lunch staple for miso soup, stews and curry. Zojirushi Japan’s current soup jar line is the SW-KA series in 300, 400 and 520 mL, with a roughly 7 cm mouth, Japan-market colors like matte green, beige and ice gray, and a one-piece “seamless” lid and gasket. Thermos Japan has sold its own 500 mL soup jars, such as the JEB-500 (now discontinued), rated at 61 °C or higher after 6 hours. These are Japan-market models, not the US SW-EAE50 or Stainless King.
Japanese reviewers on Rakuten and Kakaku.com often say the SW-KA keeps soup warm until lunch, especially if the jar is preheated with hot water, and like its wide mouth and few parts; one recurring gripe is that the large lid is hard to open one-handed. (Third-party reviews, not our own testing.)
SW-EAE50 vs Thermos Stainless King 16 oz: Frequently Asked Questions
Which food jar keeps food hotter?
No one can say from official specs. Zojirushi lists 147°F after 6 hours and Thermos lists “up to 9 hours hot.” Those are different kinds of ratings.
Is the Thermos Stainless King dishwasher safe?
Thermos says yes, top rack only.
Does the Zojirushi SW-EAE50 come with a spoon?
No spoon is listed on Zojirushi’s product page.
Which one holds more?
The SW-EAE50, by about an ounce: 17 oz vs 16 oz.
Should I preheat?
Thermos recommends preheating with boiling water for 5 minutes before filling with hot food.
Is the Thermos Stainless King 16 oz food jar recalled?
Only some units. The April 2026 recall covers SK3000 (16 oz) and SK3020 (24 oz) jars made before July 2023 whose stopper has no center pressure relief. Thermos says jars with a pressure-relief stopper aren’t covered, and its current 16 oz jar lists one.
Check current listings
Prices and colors change often, so check the current listing before buying.
Related comparisons
- Zojirushi SW-EAE35 vs SW-EAE50: 12 oz or 17 oz Food Jar?
- Zojirushi SW-KA40 vs SW-EAE50: Which Food Jar to Buy?
- Zojirushi SW-KA30 vs Thermos FUNtainer 10 oz: Kids’ Jars
- Thermos Icon 16 oz vs Zojirushi SW-EAE50: Which Food Jar?
Sources
- Zojirushi, Stainless Steel Food Jar SW-EAE35/50 (official): https://www.zojirushi.com/app/product/sweae
- Thermos, 16oz Stainless King Food Jar (official): https://thermos.com/products/stainless-king-food-jar-16oz
- Zojirushi Japan: SW-KA soup jar specs (zojirushi.co.jp): https://www.zojirushi.co.jp/syohin/bento/soup_jar/sw-ka/
- Thermos Japan: JEB-500 soup jar specs (thermos.jp): https://www.thermos.jp/product/detail/jeb-500.html
- Rakuten user reviews: Zojirushi SW-KA40 (Japanese): https://review.rakuten.co.jp/item/1/405752_10000164/1.1/
- Kakaku.com: Zojirushi SW-KA40 reviews (Japanese): https://kakaku.com/item/K0001480100/
- U.S. CPSC, Thermos Stainless King recall notice (April 30, 2026): https://www.cpsc.gov/Recalls/2026/Thermos-Recalls-8-2-Million-Stainless-King-Food-Jars-and-Bottles-Due-to-Serious-Impact-Injury-and-Laceration-Hazards
- Thermos, Product Recall page (official): https://thermos.com/pages/product-recalls
Specs checked October 2026. Prices and availability change, so check the current listing before buying.
