# How to use SPARQL `explain` to analyze Neptune query execution
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The SPARQL `explain` feature is a self-service tool in Amazon Neptune that helps you understand the execution approach taken by the Neptune engine. To invoke `explain`, you pass a parameter to an HTTP or HTTPS request in the form `explain=mode`.

The mode value can be one of `static` `dynamic`, or `details`:
+ In *static* mode, `explain` prints only the static structure of the query plan.
+ In *dynamic* mode, `explain` also includes dynamic aspects of the query plan. These aspects might include the number of intermediate bindings flowing through the operators, the ratio of incoming bindings to outgoing bindings, and the total time taken by operators.
+ In *details* mode, `explain` prints the information shown in `dynamic` mode plus additional details such as the actual SPARQL query string and the estimated range count for the pattern underlying a join operator.

Neptune supports using `explain` with all three SPARQL query access protocols listed in the [W3C SPARQL 1.1 Protocol](https://www.w3.org/TR/sparql11-protocol/#query-operation) specification, namely:

1. HTTP GET

1. HTTP POST using URL-encoded parameters

1. HTTP POST using text parameters

For information about the SPARQL query engine, see [How the SPARQL query engine works in Neptune](sparql-explain-engine.md).

For information about the kind of output produced by invoking SPARQL `explain`, see [Examples of invoking SPARQL `explain` in Neptune](sparql-explain-examples.md).