The S&P 500 has risen less than 1% since the beginning of the year, but plenty of stocks posted double-digit gains during that time. Let's take a closer look at three stocks that have rallied about 20% in January -- Shopify (SHOP 0.23%), Box (BOX 0.76%), and Workday (WDAY -1.34%) -- and see if they can continue rising through the rest of the year.

Image source: Getty Images.

Shopify

Shopify provides a cloud-based e-commerce platform for small to medium-sized businesses. Its software enables companies to design, set up, and run their own online stores, and lets them accept credit cards, view incoming orders, and review completed transactions.

Shopify's 18% rally in January is a continuation of its 150% rally over the past 12 months. That rally can be attributed to its impressive top-line growth -- its revenue surged 89% annually, to $99.6 million last quarter, following four straight quarters of 90%+ growth.

Shopify served over 325,000 merchants at the end of last quarter, which was a big jump from its customer base of "over 200,000" merchants in the prior-year quarter, and its gross merchandise volume doubled to $3.8 million. It also announced deeper integration with Amazon's sales channel earlier this month, making it easier for its customers to sell products on the e-commerce giant's marketplace.

Analysts expect Shopify's revenue to rise 86% for the full year, but it still isn't profitable yet on a GAAP or non-GAAP basis. Its GAAP loss widened last quarter, mainly due to higher stock-based compensation expenses, but its non-GAAP loss slightly narrowed. Shopify is a pretty pricey stock at 13 times sales, but its growth trajectory might support that valuation.

Box

Box provides online file sharing and personal cloud content for businesses. The company faces tough challenges in the cloud-storage market from Dropbox and bigger tech giants, but its customer base already includes massive companies like General Electric and Symantec.

Like Shopify, Box has great top-line growth and weak bottom-line growth. Its revenue rose 31% annually, to $102.8 million last quarter, as billings rose 26%. Deferred revenue, a key indicator of future demand, jumped 36%, to $192.6 million. Box's quarterly revenues have now risen by more than 30% annually for the past five quarters, and analysts anticipate 31% sales growth this year. Box is unprofitable by both GAAP and non-GAAP metrics, but its losses are narrowing by both measures.

Image source: Getty Images.

Box has rallied 23% in January, but still trades at six times sales, which is only slightly higher than the industry average of four for application-software companies. But looking ahead, Box and Dropbox both face very tough competition in the cloud-storage market.

Companies like Microsoft (MSFT -1.27%) are offering plenty of free and cheap storage to enterprise customers to tether them to their cloud ecosystems. Despite that competition, Microsoft has integrated Box into Office 365, sparking rumors of an eventual takeover. With an enterprise value of just over $2 billion, Box could certainly be a lucrative target in a consolidation of the cloud-storage market.

Workday

Workday provides enterprise cloud applications that help companies staff, pay, and organize their workforces. They also utilize analytics and machine learning to help companies make financial and workforce-related decisions.

Demand for these services has been robust -- Workday's sales rose 34% annually last quarter and have risen 30% to 40% over the past four quarters. Analysts expect its revenue to rise 35% this year, although the company warned in early January that a few of its bigger deals had been delayed by global uncertainties regarding Brexit, the U.S. presidential election, and other G8 country elections.

But like Shopify and Box, Workday has weak profitability. That's because the cost of securing new customers coupled with price competition and the low margins of the cloud SaaS (software as a service) market make it tough to squeeze out a profit, even with double-digit sales growth. Workday squeezed out a narrow non-GAAP profit last quarter, but its GAAP earnings remain deep in the red. Its price-to-sales ratio of 11 also looks pricey relative to its software-industry peers.

However, Workday stock recently rallied after Wal-Mart (WMT 0.46%) subscribed to its Human Capital Management, Recruiting, Learning, and Planning products. That deal might add $100 million to $200 million to Workday's annual revenues (5%-10% of its projected revenues for next year), according to Drexel Hamilton analyst Brian White -- but Wal-Mart didn't disclose how many of its 2 million+ employees would actually use the system. Nonetheless, that rally lifted Workday stock 24% in January.

Should you buy these stocks?

Shopify, Box, and Workday are all fairly high-risk growth stocks. I believe that Box's lower valuation and buyout potential make it the "safest" stock on this list, while Shopify's incredible top-line growth makes it the best growth play. Workday is also a good growth play, but its weak profitability and high valuations make it a risky bet for a frothy market.