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Yahoo! Developer Network - Frequently Asked Questions

Here is a list of the most common questions we get asked with their answers. If you don't find an answer to your question please contact us.

Q: What are Yahoo! Web Services?

Web Services are a way for application developers to access content and services to build new applications. For example, you can combine our data and services with those you create in a desktop application or those offered by other Web sites. With Yahoo! Web Services, more of the power of the Yahoo! network is in your hands.

Q. Who are Yahoo! Web Services for?

Yahoo! Web Services are for developers, businesses and researchers interested in using Yahoo! products, services, data and content as a resource in their applications. Right now, this program is free, subject to no SLA or uptime agreement, and subject to daily limits on query volume. If your requirements are above and beyond our standard non-commercial usage policies, please contact us and tell us how we can help your business grow.

Q: What are the guidelines and limitations for applications using Yahoo! Web Services?

All of our Web Services are available for use up to the standard per-service rate limit in applications and web sites that comply with our Terms of Use. Many of our Web Services will allow certain kinds of business usage, but this can vary per-service. You can review our general Usage Policies for more information about what is permitted.

Q: Does it cost anything to use Yahoo! Web Services?

No. We do not charge for access to our Web Services. We make them available for free to you as-is, rate limited, and controlled by the relevant Terms of Use. You may use the services up to their individual standard daily rate limit (see the documentation for specifics) in applications that comply with our Usage Policies.

Q: What do I need to access Yahoo! APIs?

To access Yahoo! Web Services, we require that you register and use an API Key (sometimes referred to as application ID), which is tied to your application. Your application ID must be sent with each Web Services request. Your application must also follow our Usage Policy and include attribution.

Q: What is an Application ID?

An Application ID is a string that uniquely identifies your application. Think of it like a User-Agent string. If you have multiple applications, you must use a different ID for each one. Get yours here.

Q: What are the limits on how much I can use Yahoo! Web Services?

Access is rate limited based on the caller's IP address, and queries are limited per IP and per day. Each service may have a different access rate limit. See the documentation for each service for more information. Circumvention of these rate limits by any means is expressly forbidden under our Terms of Use .

Q: How will I know when I hit the daily limit?

When a rate limit has been exceeded, the HTTP request will receive an error code of 403; along with a standard XML error response. See our rate limiting documentation for details.

Q: How do I request additional queries?

You can request additional queries for your application via this form. However, not all requests can be approved at this time.

Q: What is the limit on the number of results I can receive per query?

Each service may have different limits on the number of results returned by each query, as well as other variations in supported parameters. The documentation for each service specifies the default number and maximum number you can receive.

Q: Can I request more results or other changes to API behavior?

It is impossible for us to give you custom access to variations of our publicly available services. We cannot grant you more results, more parameters, more points or otherwise modify the behavior of the Web Services made available through Yahoo! Developer Network. However, we are interested in what you'd like to see in our APIs. You can use our registration form to describe your feature request or send email to the developer support mailing lists .

Q: What if the service I'm interested in isn't listed?

We support only the Web Services, APIs, and feeds launched officially on the Yahoo! Developer Network site. If you don't find the service or data you are interested in, it's not something we can make available at this time. However, by contacting us, you can cast your vote for this service and help us learn more about what tools will help you. We launch new stuff all the time, so don't give up hope! Your vote counts.

Q: What if my requirements go above and beyond the Usage Policies?

Please contact us if you would like to speak with someone about usage requirements beyond our standard non-commercial limitations. We would love to learn how Yahoo! can help your business succeed.

Q: Some of your services say "non-commercial use only". What does that mean?

Some of our services are made available only for use in non-commercial applications. For those services, we are not able to place firm limits on what we consider "commercial use" because so many unforeseen uses are invented daily that we need to maintain a level of flexibility - especially while the program is free. That said, below are general examples of uses we consider to be commercial:

  • Use of our services on high traffic, established commercial-oriented or business web sites or applications
  • Applications or web sites monetized indirectly (by advertising, affiliate links) or directly, including subscriber-only content (subscriptions, software-as-a-service, hosted applications where your users pay for access) and for-pay applications, products or services
  • Productivity tools for businesses created to bring value to a business function, typically only accessible to select users

Developers can create applications that use our APIs and web services as work-for-hire for clients, however the usage within application itself must be approved.

Q: Where can I get help with Yahoo! Web Services?

Help is available on our developer support mailing lists hosted by Yahoo! Groups.

Q: Where do I report bugs or outages while using Yahoo! Web Services?

The best place to report bugs, outages or unexpected behavior is by posting to the developer support forums for the Web Service in question.

Q: Can I get driving directions using Yahoo! Maps?

At this time we don't offer an API to access our driving direction data. For a workaround, you can generate a link to a Yahoo! Map from which you can easily click to driving directions. See this Yahoo! Maps help page for guidance in forming your query string.

Q: What is REST?

REST stands for Representational State Transfer. Most of the Yahoo! Web Services use "REST-Like" RPC-style operations over HTTP GET or POST requests with parameters URL encoded into the request.

For more information about REST please check out the following:

Q: What is the version number on each service for?

The API for each service is versioned. When we need to change it or want to add functionality, we will release a new version of the API. Multiple versions of each API may coexist — you'll use the version part of the API URL to specify which one you intend to access. See the versions documentation for more information.

Q: What programming languages does Yahoo! support?

You can use any language you like. Our SDK provides libraries and/or examples in various languages.

Q: What is in the developer's kit?

The SDK contains code and documentation to help you get started with the Yahoo! Search Web Services. There are libraries for accessing our services in Perl, Java, and Python, and code examples for JavaScript and PHP. Note that currently the SDK supports only the Yahoo! Search Web Services although the examples may be helpful for other Yahoo! Web Services has well.

Q: Does Yahoo! support Macromedia® Flash development using the Yahoo! Search APIs?

To help you use Yahoo! Search APIs in your Flash applications, we have added a crossdomain.xml file to the top level of the Search Web Services directory. This should enable your Flash-based applications to retrieve data from the Web Services.

Q: Does Yahoo! plan to support SOAP?

Not at this time. We may provide SOAP interfaces in the future, if there is significant demand. We believe REST has a lower barrier to entry, is easier to use than SOAP, and is entirely sufficient for these services.

Q: While using the Yahoo! Search APIs, what's the difference between a "click URL" and "display URL"?

Our services often provide two URLs for each result. The "display URL" leads directly to the site or resource in question. It's suitable for display in an application. The "click URL" is longer and contains extra information that helps us to optimize our search services.

Please use the click URL when sending users to a site as the result of using our services. For example, <a href="$clickUrl">$displayUrl</a>

Q: Why does ColdFusion keep giving me a "Connection Failure" message?

It's an encoding issue. You need to add <cfhttpparam type="Header" name="charset" value="utf-8" /> to your cfhttp call and it should work.

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