Best Round Bottom Lab Flasks of 2026

Tom Law Avatar
Tom Law
Last Updated: 2 Feb 2026

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Round bottom lab flasks are essential tools in any laboratory setting. These flasks are designed with a round bottom to allow for easy mixing and swirling of liquids, making them ideal for a variety of applications such as chemical reactions, titrations, and distillations. Made from high-quality borosilicate glass, these flasks are durable and can withstand high temperatures and chemical reactions. They are available in various sizes and shapes to suit different experimental needs. The round bottom lab flasks are a must-have for any laboratory looking to achieve accurate and reliable results.

At a Glance: Our Top Picks

StonyLab 500ml Borosilicate Glass Flask Cover #TOP 1
StonyLab 500ml Borosilicate Glass Flask
ftb score rating icon 9.8
KING SCIENTIFIC 500ML Borosilicate Glass Flask Cover #TOP 2
KING SCIENTIFIC 500ML Borosilicate Glass Flask
ftb score rating icon 9.7
StonyLab 250ml Long Neck Round Bottom Flask Cover #TOP 3
StonyLab 250ml Long Neck Round Bottom Flask
ftb score rating icon 9.5

Top 4 Round Bottom Lab Flasks

StonyLab 500ml Borosilicate Glass Flask

US-RBF-3Neck-Glass-500ml
Transparent
500 ml
StonyLab 500ml Borosilicate Glass Flask Cover
StonyLab Borosilicate Glass 3 Neck Round Bottom Flask RBF, with 24/40 Center and Side Standard Taper Outer Joint – 500ml

The StonyLab Round Bottom Flask is an essential tool for any laboratory setting. With its three angled necks, you can easily connect multiple pieces of equipment, making your experiments more efficient. Constructed from durable borosilicate glass, it can withstand temperatures up to 200°C, ensuring reliability during heating processes. The 24/40 centre joint allows for standard compatibility with other lab apparatus, providing you with versatility in your work. This flask is perfect for a variety of applications, helping you achieve precise results with ease.

What We Like
Durable borosilicate glass
Three angled necks
Standard 24/40 joint
Temperature resistant up to 200°C
#TOP 2

KING SCIENTIFIC 500ML Borosilicate Glass Flask

KING SCIENTIFIC 500ML Borosilicate Glass Flask Cover
KING SCIENTIFIC 500ML HEAVY DUTY BOROSILICATE GLASS ROUND FLASK FLAT BOTTOM

The KING SCIENTIFIC Glass Flask is designed with a 500ml capacity, making it ideal for various laboratory applications. Its flat bottom ensures stability, allowing you to work efficiently without the risk of tipping. Crafted from durable borosilicate glass, this flask can withstand high temperatures and is resistant to thermal shock. The narrow beaded neck provides a secure grip, making it easier for you to handle the flask without spills. Overall, this flask offers a practical and cost-effective alternative to other brands.

What We Like
Durable borosilicate glass
Stable flat bottom
Narrow beaded neck
Cost-effective compared to Pyrex
Multiple brands available
#TOP 3

StonyLab 250ml Long Neck Round Bottom Flask

B07ZD14HY9
250ml
250 ml
StonyLab 250ml Long Neck Round Bottom Flask Cover
StonyLab Glass 250ml Long Neck Round Bottom Flask, Borosilicate Glass Heavy Wall Round Bottom Boiling Flask RBF with Long Neck - 250ml

The StonyLab Round Bottom Flask is designed for high-temperature applications, with a maximum temperature resistance of 200°C. Constructed from durable borosilicate glass, this flask offers excellent thermal stability, making it ideal for boiling and other laboratory processes. Its long neck design facilitates easy handling and pouring, providing convenience during experiments. With a capacity of 250 ml, it is suitable for various applications, allowing you to measure and mix liquids with precision.

What We Like
Durable borosilicate glass
High-temperature resistance
Convenient long neck design
250 ml capacity
#TOP 4

StonyLab Heavy Wall Borosilicate Kjeldahl Flask 100ml

KjeldahlFlask-24/40-100ml
100 ml
StonyLab Heavy Wall Borosilicate Kjeldahl Flask 100ml Cover
stonylab Kjeldahl Flask, Heavy Wall Long Neck Lab Flask Borosilicate Glass Round Bottom Kjeldahl Flask with 24/40 Standard Taper Outer Joint, 100 ml

The StonyLab Kjeldahl Flask is designed to assist you during the Kjeldahl process, particularly as an air condenser in the digestion stage, helping to improve efficiency. Its 100 ml capacity is ideal for precise measurements in your laboratory work. The flask features a 24/40 standard taper outer joint, ensuring a secure and standard connection with other lab equipment. Made from heavy-duty borosilicate glass, it offers excellent durability and can withstand temperatures up to 200°C, making it a reliable choice for various lab applications.

What We Like
Heavy-duty borosilicate glass
100 ml capacity
24/40 standard taper joint
Withstands temperatures up to 200°C
Buying Guide Image
Editor's Notes

During our round bottom lab flask research, we found 267 round bottom lab flask products and shortlisted 4 quality products. We collected and analyzed 3,626 customer reviews through our big data system to write the round bottom lab flasks list. We found that most customers choose round bottom lab flasks with an average price of £20.00.

The round bottom lab flasks are available for purchase. We have researched hundreds of brands and picked the top brands of round bottom lab flasks, including stonylab, KING SCIENTIFIC.

Written by
Tom Law Avatar

Tom Law is an adventurer who has captured his love for nature into all of his works. A native of Newcastle, Tom has always wanted to share beautiful stories alongside the lovely sights of nature. Fortunately, he took into photography on one of his many journeys and gradually grew a passion for it. Tom Law is now an expert photographer who tours the world while creating and keeping memories of his adventures. He frequently puts his thoughts and experiences into writing.