How to choose a survey tool
Start with response volume, not features. Almost every tool on this list can ask a multiple choice question. What separates them is what happens at scale: SurveyMonkey's entry paid plan includes 15,000 responses a year, SurveySparrow's Basic gives 2,500, and Survicate counts both responses and data points separately. Estimate your annual responses first and the shortlist gets much shorter.
Logic and branching
Skip logic sends a respondent past questions that do not apply to them, and it is the single biggest factor in completion rate on anything longer than five questions. SurveyMonkey, SurveySparrow and Jotform all include it on paid plans. Google Forms has a simpler version that branches on section, which covers a screening question but not much more.
Where the survey lives
A link you email is not the same product as a widget that appears inside your app. Survicate and SurveySparrow are built around in-product and in-email surveys, which is why they cost more per response. Outgrow is a different animal again: it makes calculators, quizzes and interactive content aimed at generating leads rather than gathering opinions, so compare it against a landing page builder as much as against a survey tool.
What the free plans actually give you
Google Forms is genuinely free and unlimited, which no commercial tool matches, and for an internal poll or an event signup it is usually the right answer. The commercial free tiers are demos: SurveyMonkey Basic caps you at 10 questions per survey, Jotform Starter at 5 forms and 100 submissions a month, and Mailchimp's free tier is an email plan that happens to include forms. Treat them as a way to test the builder, not as a plan to run on.
Do not overlook exports
If your analysis happens in a spreadsheet or a BI tool, check the export before you commit. Most paid plans give CSV and XLSX; crosstabs, weighting and statistical significance testing are higher tier features on SurveyMonkey and absent from the cheaper tools entirely.