diff --git a/README.md b/README.md
index a101ffa..2b9d705 100644
--- a/README.md
+++ b/README.md
@@ -449,7 +449,7 @@ supports the HTTP/2 protocol, in addition to many other features.
 
 ```rb
 gem "down", "~> 5.0"
-gem "httpx", "~> 0.22"
+gem "httpx", "~> 1.0"
 ```
 ```rb
 require "down/httpx"
diff --git a/down.gemspec b/down.gemspec
index 4f1e0e2..a2092f3 100644
--- a/down.gemspec
+++ b/down.gemspec
@@ -20,7 +20,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "minitest", "~> 5.8"
   spec.add_development_dependency "mocha", "~> 1.5"
   spec.add_development_dependency "rake"
-  spec.add_development_dependency "httpx", "~> 0", "< 2.0.0"
+  spec.add_development_dependency "httpx", RUBY_VERSION >= "2.7" ? "~> 1.0" : "~> 0.24"
   spec.add_development_dependency "http", RUBY_VERSION >= "2.5" ? "~> 5.0" : "~> 4.3"
   spec.add_development_dependency "warning"
   spec.add_development_dependency "csv"