When Was the First Microwave Sold? History & Facts

Introduction

Few kitchen appliances have changed daily life as completely as the microwave oven. Today, it is hard to imagine a modern kitchen, office break room, or dorm room without one. Yet for most of human history, cooking required fire, heat, and patience. The microwave introduced something entirely new: cooking with electromagnetic waves. Because the appliance is so common now, many people assume it has always been affordable and compact. The truth is far more interesting.

This article answers the question when was the first microwave sold? and traces the journey from a bulky, water-cooled commercial machine to the countertop appliance found in millions of homes. You will learn who invented it, how much the earliest models cost, where they were first used, and how microwave technology moved from restaurants and trains into ordinary kitchens. Along the way, we will separate fact from myth and offer practical guidance for anyone curious about vintage microwave history.

Table of Contents

• Introduction
• When Was the First Microwave Sold?
• The Invention of Microwave Technology
• The First Commercial Microwave Oven
• Early Adoption in Restaurants and Trains
• The Move to Home Kitchens
• How the First Microwave Oven Worked
• Comparison of Early Microwave Models
• Cultural Impact and the Kitchen Revolution
• Common Misconceptions About Microwave History
• Tips for Identifying Vintage Microwaves
• Safety Best Practices for Older Microwaves
• Frequently Asked Questions
• Conclusion

When Was the First Microwave Sold?

The short answer is that the first commercial microwave oven was sold in 1947. The manufacturer was Raytheon, and the product was called the Radarange. It was not a small countertop device. It stood nearly six feet tall, weighed about 750 pounds, required water cooling, and cost the equivalent of tens of thousands of dollars in today’s money. Because of its size and price, the first microwave was sold exclusively to restaurants, hotels, and other institutions, not to private homeowners.

If you are asking when the first microwave was sold for home use, the answer is different. The first household microwave oven appeared in 1955, but it remained a luxury item for well over a decade. It was not until 1967 that a relatively affordable countertop model brought microwave cooking within reach of average families. So, depending on whether you mean commercial or residential sales, the date changes. This article covers both milestones in detail.

The Invention of Microwave Technology

The story begins during World War II, when engineers were developing radar systems to detect enemy aircraft and ships. A key component of these systems was the magnetron, a vacuum tube that generates microwaves. Raytheon was one of the major companies producing magnetrons for the military, and one of its employees, Percy Spencer, would accidentally change the way the world cooks food.

According to the widely accepted account, Spencer was standing near an active radar set in 1945 when he noticed that a chocolate bar in his pocket had melted. Curious, he tested other foods. Popcorn kernels popped, and an egg exploded when it heated too quickly inside its shell. Spencer realized that microwaves could cook food by exciting water molecules, and he began experimenting with ways to contain and direct the energy safely.

Raytheon filed a patent for Spencer’s microwave cooking method, and the company soon moved from laboratory curiosity to commercial product. The invention was not the result of a plan to revolutionize home cooking. It was a byproduct of wartime research that found an unexpected peacetime application.

The First Commercial Microwave Oven

Raytheon introduced the first commercial microwave oven, the Radarange, in 1947. This machine bore little resemblance to the appliances sold today. It was roughly the size of a refrigerator, required plumbing for water cooling, and needed a dedicated electrical connection. Restaurants and institutions were the only buyers who could accommodate such demands.

The first Radarange units sold for between $2,000 and $3,000, an enormous sum at the time. Adjusted for inflation, that would be tens of thousands of dollars today. Despite the cost, the machine offered something conventional ovens could not: speed. It could reheat or cook certain foods in a fraction of the time, which made it attractive to high-volume kitchens.

Because the Radarange was designed for commercial use, it featured heavy-duty construction and simple controls. There were no digital displays or preset buttons. Operators relied on timers and manual adjustments. The first microwave sold in 1947 marked the beginning of an industry, but it would take years before the technology shrank enough and became cheap enough for the average household.

Early Adoption in Restaurants and Trains

In the late 1940s and early 1950s, microwave ovens appeared primarily in commercial settings. Restaurants used them to reheat pre-cooked meals and to prepare items quickly during busy service. Some railroads experimented with microwave ovens in dining cars, where space was limited and speed was essential. Hotels and airlines also showed interest in the technology for similar reasons.

Early adoption was slow for several reasons. First, the price was prohibitive for all but the largest establishments. Second, many chefs and restaurant owners distrusted the new method. They worried that food cooked by invisible waves would taste strange or lose quality. Third, the machines required maintenance and technical knowledge that many kitchens did not have.

Still, the commercial success of the Radarange proved that microwave cooking worked. It paved the way for engineers to miniaturize the magnetron, simplify the controls, and reduce the power requirements. Without those early commercial sales, there might not have been enough incentive to develop a home version.

The Move to Home Kitchens

The transition from commercial to residential use happened in stages. In 1955, the Tappan Stove Company introduced what is often considered the first microwave oven designed for the home. It was a built-in wall unit that required 220 volts of electricity and sold for about $1,295. Only wealthy homeowners with modern kitchens could realistically purchase one, and sales remained limited.

The real breakthrough came in 1967, when Amana, a division of Raytheon, released the first countertop Radarange for home use. It operated on standard 115-volt household current, weighed roughly 100 pounds, and cost around $495. While still expensive by the standards of the time, it was a fraction of the price of earlier models and could fit on an existing kitchen counter.

From that point forward, microwave sales grew steadily through the 1970s and 1980s. Manufacturers added features such as digital timers, defrost settings, and rotating glass trays. Prices continued to fall, and by the end of the 20th century, the microwave oven had become a standard fixture in most American homes.

How the First Microwave Oven Worked

Understanding how the earliest microwave ovens operated helps explain why they were so large and expensive. The process relies on converting electrical energy into electromagnetic waves that excite water molecules in food. Below is a step-by-step overview of the basic process used by the first commercial microwave ovens.

1. Electricity powers the magnetron. When the oven is switched on, high-voltage electricity flows to the magnetron tube. The magnetron converts this energy into microwave radiation, typically at a frequency around 2450 megahertz.
2. Microwaves travel through the waveguide. The waves move from the magnetron through a metal channel called a waveguide. This channel directs the energy toward the cooking cavity without allowing it to escape into the surrounding room.
3. Waves enter the cooking chamber. Inside the oven, the microwaves bounce off the metal walls and penetrate the food. The metal enclosure keeps the waves contained so they can do their work efficiently.
4. Water molecules vibrate and generate heat. Microwaves cause polar molecules, especially water, to rotate rapidly. This molecular motion creates friction, which produces heat throughout the food. This is why foods with high water content tend to heat quickly.
5. Controls regulate cooking time. Early models used mechanical timers and simple power switches. The operator set the duration, and the magnetron ran until the timer expired. There were no sensors or computerized presets in the first units.
6. Safety interlocks stop the magnetron. When the door is opened, mechanical interlocks cut power to the magnetron immediately. This prevents microwaves from leaking out while the oven is in use or being loaded.

These steps remain fundamentally the same in modern microwave ovens, although today’s components are smaller, safer, and far more efficient than those used in the 1940s.

Comparison of Early Microwave Models

To see how quickly microwave technology changed, it helps to compare the first commercial model with the first home models. The table below highlights key differences among three landmark ovens.

Model	Year	Type	Approximate Price	Power Requirement	Size and Weight	Primary User
Raytheon Radarange	1947	Commercial	$2,000–$3,000	Commercial electrical and water cooling	About 6 feet tall; roughly 750 pounds	Restaurants and institutions
Tappan Home Microwave	1955	Built-in wall oven	$1,295	220-volt household current	Large built-in unit	Wealthy homeowners
Amana Countertop Radarange	1967	Countertop	$495	Standard 115-volt household outlet	About 100 pounds; countertop footprint	Average households

This comparison shows why the 1967 Amana model is often remembered as the first truly accessible microwave oven. It removed the need for special plumbing or high-voltage wiring, making it practical for ordinary kitchens.

Cultural Impact and the Kitchen Revolution

When the first microwave was sold in 1947, few people could have predicted how thoroughly it would reshape everyday eating habits. The appliance introduced a new idea: that cooking did not have to take time. Reheating leftovers, preparing frozen meals, and popping popcorn became tasks measured in seconds rather than minutes.

The microwave also influenced food manufacturing. Companies developed products specifically for microwave cooking, from frozen dinners to microwaveable popcorn bags. Packaging changed to include heating instructions, and grocery stores created entire freezer sections devoted to microwave-ready foods. The appliance became a symbol of modern convenience, even as some critics worried it encouraged reliance on processed food.

Public perception evolved slowly. Early consumers sometimes feared that microwave radiation might make food radioactive or harm their health. Over time, scientific evidence and widespread use eased most of those concerns. Today, the microwave is viewed as an ordinary tool rather than a futuristic invention, but its origins in radar technology remain a remarkable chapter in kitchen history.

Common Misconceptions About Microwave History

Several myths persist about the first microwave oven and how it came to be. Clearing them up provides a more accurate picture of the technology’s development.

Myth: The first microwave was sold in 1967. This is only true if you mean the first affordable countertop model for home use. The first commercial microwave was sold two decades earlier, in 1947.

Myth: Percy Spencer set out to invent a cooking appliance. Spencer was working on radar equipment when he noticed the heating effect. The cooking application was an accidental discovery, not the original goal.

Myth: Microwaves cook food from the inside out. Microwaves penetrate food to a limited depth, and the interior is often heated by conduction from the outer layers. Thick foods can have cold centers even when the outside is hot.

Myth: Microwaves make food radioactive. Microwave radiation is non-ionizing. It heats food but does not leave residual radiation or make the food itself radioactive.

Understanding these distinctions helps readers evaluate historical claims and avoid repeating outdated information.

Tips for Identifying Vintage Microwaves

If you come across an old microwave oven and want to know whether it is a genuine vintage model, there are several practical clues to check. These tips can help you distinguish early commercial units from later home appliances.

• Check the brand and model number. Raytheon, Amana, and Tappan are among the most important early manufacturers. A metal nameplate or sticker usually lists this information.
• Look at the size and weight. Commercial units from the 1940s and 1950s are enormous and heavy compared with modern microwaves. A unit that requires two people to move may date from the early commercial era.
• Examine the controls. Early models typically have mechanical dials, timers, and toggle switches. Digital touchpads did not become common until much later.
• Inspect the power requirements. Units that require 220 volts or water cooling are almost certainly pre-1960s commercial equipment.
• Research the serial number. Manufacturers and collector groups often maintain records that can confirm a model’s production year.

Identifying a vintage microwave can be rewarding, but it is also important to remember that old electrical appliances may not meet modern safety standards.

Safety Best Practices for Older Microwaves

Using or preserving an older microwave oven requires caution. Technology and safety standards have changed significantly since the first microwave was sold, and early units lack many protections found in modern appliances.

• Never operate an empty microwave. Running the oven without food or liquid can damage the magnetron and create a fire hazard.
• Inspect the door seal and hinges. A damaged door or worn seal can allow microwave energy to leak. If the door does not close firmly, do not use the oven.
• Avoid metal objects. Metal can cause arcing and damage the interior. This applies to foil, twist ties, and dishes with metallic trim.
• Check the power cord and plug. Old cords may be frayed or brittle. Replace damaged cords only with proper appliance-grade replacements, or consult a qualified technician.
• Consider professional testing. If you plan to use a vintage microwave regularly, have a technician test for radiation leakage and electrical safety.

These precautions apply especially to commercial units from the 1940s and 1950s, which were not designed with today’s consumer safety features in mind.

Frequently Asked Questions

When was the first microwave sold?

The first commercial microwave oven was sold in 1947 by Raytheon under the Radarange name. It was intended for restaurants and institutions, not for home kitchens.

Who invented the microwave oven?

Percy Spencer, an engineer at Raytheon, is credited with discovering the cooking potential of microwaves while working on radar equipment during World War II.

Was the first microwave sold for home use?

No. The first microwave sold in 1947 was a large commercial unit. The first home microwave appeared in 1955 from Tappan, and the first popular countertop home model arrived in 1967 from Amana.

How much did the first microwave cost?

The early commercial Radarange sold for roughly $2,000 to $3,000 in 1947, which would be tens of thousands of dollars today. The 1967 Amana countertop model cost about $495.

When did microwaves become common in homes?

Microwaves began appearing in more homes after 1967, but they did not become a standard kitchen appliance until the 1970s and 1980s as prices dropped and sizes shrank.

Is it safe to use a vintage microwave?

A vintage microwave can be safe if the door seals properly, the cord is in good condition, and the unit has been tested for leakage. However, old appliances should be inspected before regular use.

Do microwaves make food radioactive?

No. Microwave ovens use non-ionizing radiation to heat food. They do not leave residual radiation in the food or make it radioactive.

Conclusion

The answer to when was the first microwave sold? depends on whether you mean commercial or residential use. The first commercial microwave oven went on sale in 1947, while the first practical home model arrived two decades later. From a six-foot-tall, water-cooled machine to a compact countertop appliance, the microwave evolved through engineering improvements, lower costs, and growing consumer acceptance.

Knowing this history adds context to an appliance most people use without thinking. It also reminds us that transformative technology often begins in unexpected places, such as a radar laboratory during wartime. If you are researching vintage models or simply curious about kitchen history, the key milestones are 1947 for commercial sales, 1955 for the first home unit, and 1967 for the first affordable countertop oven.

The microwave oven remains one of the most influential inventions of the modern kitchen. Understanding where it came from helps appreciate how far it has come.