# Calculating Download MD5 Hash

DevFeed: [Calculating Download MD5 Hash](<https://devfeed.tech/articles/calculating-download-md5-hash-22216.md>)

Original publisher: [Read original article](<https://www.ardanlabs.com/blog/2023/03/calculating-download-md5-in-go.html>)

Published: 2023-03-09T00:00:00Z

Content type: tutorial

Language: en

Sources: [William Kennedy](<https://devfeed.tech/sources/william-kennedy.md>)

Topics: [Go Language](<https://devfeed.tech/topics/go-language.md>), [HTTP](<https://devfeed.tech/topics/http.md>), [cURL](<https://devfeed.tech/topics/curl.md>), [Google Cloud Platform (GCP)](<https://devfeed.tech/topics/google-cloud.md>), [dataset](<https://devfeed.tech/topics/dataset.md>), [Code](<https://devfeed.tech/topics/code.md>)

Tags: [ardan-labs](<https://devfeed.tech/tags/ardan-labs.md>), [blog](<https://devfeed.tech/tags/blog.md>), [cloud](<https://devfeed.tech/tags/cloud.md>), [code](<https://devfeed.tech/tags/code.md>), [curl](<https://devfeed.tech/tags/curl.md>), [dataset](<https://devfeed.tech/tags/dataset.md>), [go](<https://devfeed.tech/tags/go.md>), [go-programming](<https://devfeed.tech/tags/go-programming.md>), [golang](<https://devfeed.tech/tags/golang.md>), [google-cloud](<https://devfeed.tech/tags/google-cloud.md>), [hash](<https://devfeed.tech/tags/hash.md>), [http](<https://devfeed.tech/tags/http.md>), [programming](<https://devfeed.tech/tags/programming.md>)

## AI overview

This tutorial explains how to validate a downloaded file's MD5 signature using HTTP headers and Go. It demonstrates obtaining file metadata with an HTTP HEAD request, reading the MD5 value reported by Google Cloud Storage, and implementing the request and header parsing in Go.

## Source excerpt

Introduction One of the exercises I give to students is to download a single big file over HTTP concurrently using several goroutines using HTTP Range requests. An extra part of the exercise is to validate the downloaded file from a known MD5 signature. This extra part turns out to be interesting, let's have a look. Getting Download Information Let's make an HTTP HEAD request to get information about a file located in a public dataset stored on Google Cloud Storage (GCS).