diff --git a/src/corelib/platform/wasm/qstdweb.cpp b/src/corelib/platform/wasm/qstdweb.cpp
index 84a7f0d405..b5e7212876 100644
--- a/src/corelib/platform/wasm/qstdweb.cpp
+++ b/src/corelib/platform/wasm/qstdweb.cpp
@@ -499,7 +499,7 @@ uint32_t ArrayBuffer::byteLength() const
     return m_arrayBuffer["byteLength"].as<uint32_t>();
 }
 
-emscripten::val ArrayBuffer::val()
+emscripten::val ArrayBuffer::val() const
 {
     return m_arrayBuffer;
 }
@@ -532,7 +532,7 @@ Blob Blob::copyFrom(const char *buffer, uint32_t size)
     return copyFrom(buffer, size, "application/octet-stream");
 }
 
-emscripten::val Blob::val()
+emscripten::val Blob::val() const
 {
     return m_blob;
 }
@@ -583,7 +583,7 @@ std::string File::type() const
     return m_file["type"].as<std::string>();
 }
 
-emscripten::val File::val()
+emscripten::val File::val() const
 {
     return m_file;
 }
@@ -642,7 +642,7 @@ void FileReader::onAbort(const std::function<void(emscripten::val)> &onAbort)
     m_onAbort = std::make_unique<EventCallback>(m_fileReader, "abort", onAbort);
 }
 
-emscripten::val FileReader::val()
+emscripten::val FileReader::val() const
 {
     return m_fileReader;
 }
@@ -740,7 +740,7 @@ Uint8Array Uint8Array::copyFrom(const QByteArray &buffer)
     return copyFrom(buffer.constData(), buffer.size());
 }
 
-emscripten::val Uint8Array::val()
+emscripten::val Uint8Array::val() const
 {
     return m_uint8Array;
 }
diff --git a/src/corelib/platform/wasm/qstdweb_p.h b/src/corelib/platform/wasm/qstdweb_p.h
index 42e6a22381..a59cc4c81d 100644
--- a/src/corelib/platform/wasm/qstdweb_p.h
+++ b/src/corelib/platform/wasm/qstdweb_p.h
@@ -58,7 +58,7 @@ namespace qstdweb {
         explicit ArrayBuffer(uint32_t size);
         explicit ArrayBuffer(const emscripten::val &arrayBuffer);
         uint32_t byteLength() const;
-        emscripten::val val();
+        emscripten::val val() const;
 
     private:
         friend class Uint8Array;
@@ -71,7 +71,7 @@ namespace qstdweb {
         uint32_t size() const;
         static Blob copyFrom(const char *buffer, uint32_t size, std::string mimeType);
         static Blob copyFrom(const char *buffer, uint32_t size);
-        emscripten::val val();
+        emscripten::val val() const;
         std::string type() const;
 
     private:
@@ -91,7 +91,7 @@ namespace qstdweb {
         void stream(uint32_t offset, uint32_t length, char *buffer,
                     std::function<void()> completed) const;
         void stream(char *buffer, std::function<void()> completed) const;
-        emscripten::val val();
+        emscripten::val val() const;
 
     private:
         emscripten::val m_file = emscripten::val::undefined();
@@ -119,7 +119,7 @@ namespace qstdweb {
         void onLoad(const std::function<void(emscripten::val)> &onLoad);
         void onError(const std::function<void(emscripten::val)> &onError);
         void onAbort(const std::function<void(emscripten::val)> &onAbort);
-        emscripten::val val();
+        emscripten::val val() const;
 
     private:
         emscripten::val m_fileReader = emscripten::val::global("FileReader").new_();
@@ -147,7 +147,7 @@ namespace qstdweb {
         static void copy(char *destination, const Uint8Array &source);
         static Uint8Array copyFrom(const char *buffer, uint32_t size);
         static Uint8Array copyFrom(const QByteArray &buffer);
-        emscripten::val val();
+        emscripten::val val() const;
 
     private:
         static emscripten::val heap_();