The cost of special tools or equipment for work can be expensive. Thankfully, the IRS allows you to deduct these expenses in most cases. The government considers these deductions to be ordinary and necessary for your job. The term "ordinary" refers to any expenses that are commonly accepted in your trade or industry. The term "necessary" refers to expenses that are appropriate and helpful to your job. The tools or equipment that you purchase do not have to be required for your job in order to qualify as a necessary expense.
You will have to show that the expense you incurred was for the purchase of an item that helps you perform your job or trade more efficiently. You also need to show that your employer does not provide you with the item.
Depending on your industry, there are a variety of qualifying expenses that can be deducted. For example, computers, smart phones, power tools, etc., are considered expenses necessary and ordinary and can be deducted. You have to consider the percentage of time the item is used for work purposes. If you use your computer for personal use 30% of the time, you are eligible to deduct 70% of the cost of the item as a business expense.