diff --git a/.gitmodules b/.gitmodules
index 904d869076..cc5f77d136 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -69,13 +69,6 @@ ignore = dirty
 depth = 1
 shallow = true
 fetchRecurseSubmodules = false
-[submodule "src/deps/base64"]
-path = src/deps/base64
-url = https://github.com/aklomp/base64.git
-ignore = dirty
-depth = 1
-shallow = true
-fetchRecurseSubmodules = false
 [submodule "src/deps/ls-hpack"]
 path = src/deps/ls-hpack
 url = https://github.com/litespeedtech/ls-hpack.git
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0a6b18d897..d79dfb0d3d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -301,7 +301,6 @@ option(USE_CUSTOM_LIBARCHIVE "Use Bun's recommended version of libarchive" ON)
 option(USE_CUSTOM_MIMALLOC "Use Bun's recommended version of Mimalloc" ON)
 option(USE_CUSTOM_ZSTD "Use Bun's recommended version of zstd" ON)
 option(USE_CUSTOM_CARES "Use Bun's recommended version of c-ares" ON)
-option(USE_CUSTOM_BASE64 "Use Bun's recommended version of libbase64" ON)
 option(USE_CUSTOM_LOLHTML "Use Bun's recommended version of lolhtml" ON)
 option(USE_CUSTOM_TINYCC "Use Bun's recommended version of tinycc" ON)
 option(USE_CUSTOM_LIBUV "Use Bun's recommended version of libuv (Windows only)" ON)
@@ -1333,19 +1332,6 @@ else()
     target_link_libraries(${bun} PRIVATE c-ares::cares)
 endif()
 
-if(USE_CUSTOM_BASE64)
-    include_directories(${BUN_DEPS_DIR}/base64/include)
-
-    if(WIN32)
-        target_link_libraries(${bun} PRIVATE "${BUN_DEPS_OUT_DIR}/base64.lib")
-    else()
-        target_link_libraries(${bun} PRIVATE "${BUN_DEPS_OUT_DIR}/libbase64.a")
-    endif()
-else()
-    find_package(base64 REQUIRED)
-    target_link_libraries(${bun} PRIVATE base64::base64)
-endif()
-
 if(USE_CUSTOM_TINYCC)
     if(WIN32)
         target_link_libraries(${bun} PRIVATE "${BUN_DEPS_OUT_DIR}/tcc.lib")
diff --git a/Dockerfile b/Dockerfile
index 32f17f8d89..0f7063db25 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -297,19 +297,6 @@ RUN --mount=type=cache,target=${CCACHE_DIR} \
   && make boringssl \
   && rm -rf src/deps/boringssl Makefile
 
-FROM bun-base as base64
-
-ARG BUN_DIR
-ARG CPU_TARGET
-ENV CPU_TARGET=${CPU_TARGET}
-
-COPY Makefile ${BUN_DIR}/Makefile
-COPY src/deps/base64 ${BUN_DIR}/src/deps/base64
-
-WORKDIR $BUN_DIR
-
-RUN cd $BUN_DIR && \
-  make base64 && rm -rf src/deps/base64 Makefile
 
 FROM bun-base as zstd
 
@@ -508,7 +495,6 @@ COPY src/symbols.dyn src/linker.lds ${BUN_DIR}/src/
 
 COPY CMakeLists.txt ${BUN_DIR}/CMakeLists.txt
 COPY --from=zlib ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
-COPY --from=base64 ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
 COPY --from=libarchive ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
 COPY --from=boringssl ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
 COPY --from=lolhtml ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
@@ -572,7 +558,6 @@ COPY src/symbols.dyn src/linker.lds ${BUN_DIR}/src/
 
 COPY CMakeLists.txt ${BUN_DIR}/CMakeLists.txt
 COPY --from=zlib ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
-COPY --from=base64 ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
 COPY --from=libarchive ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
 COPY --from=boringssl ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
 COPY --from=lolhtml ${BUN_DEPS_OUT_DIR}/* ${BUN_DEPS_OUT_DIR}/
diff --git a/LICENSE b/LICENSE
index 21b2b8466a..0206d2e994 100644
--- a/LICENSE
+++ b/LICENSE
@@ -92,11 +92,6 @@ Bun statically links these libraries:
 
 ---
 
-- [`libbase64`](https://github.com/aklomp/base64/blob/master/LICENSE)
-- BSD 2-Clause
-
----
-
 - A fork of [`uWebsockets`](https://github.com/jarred-sumner/uwebsockets)
 - Apache 2.0 licensed
 
diff --git a/Makefile b/Makefile
index 2a108abaaf..5ffca73ee4 100644
--- a/Makefile
+++ b/Makefile
@@ -449,8 +449,7 @@ MINIMUM_ARCHIVE_FILES = -L$(BUN_DEPS_OUT_DIR) \
 	-ldecrepit \
 	-lssl \
 	-lcrypto \
-	-llolhtml \
-	-lbase64
+	-llolhtml
 
 ARCHIVE_FILES_WITHOUT_LIBCRYPTO = $(MINIMUM_ARCHIVE_FILES) \
 		-larchive \
@@ -1971,11 +1970,6 @@ copy-to-bun-release-dir-bin:
 
 PACKAGE_MAP = --pkg-begin async_io $(BUN_DIR)/src/io/io_darwin.zig --pkg-begin bun $(BUN_DIR)/src/bun_redirect.zig --pkg-end --pkg-end --pkg-begin javascript_core $(BUN_DIR)/src/jsc.zig --pkg-begin bun $(BUN_DIR)/src/bun_redirect.zig --pkg-end --pkg-end --pkg-begin bun $(BUN_DIR)/src/bun_redirect.zig --pkg-end
 
-.PHONY: base64
-base64:
-	cd $(BUN_DEPS_DIR)/base64 && make clean && rm -rf CMakeCache.txt CMakeFiles && cmake $(CMAKE_FLAGS) . && make
-	cp $(BUN_DEPS_DIR)/base64/libbase64.a $(BUN_DEPS_OUT_DIR)/libbase64.a
-
 .PHONY: cold-jsc-start
 cold-jsc-start:
 	$(CXX_WITH_CCACHE) $(CLANG_FLAGS) \
@@ -1993,7 +1987,7 @@ cold-jsc-start:
 		misctools/cold-jsc-start.cpp -o cold-jsc-start
 
 .PHONY: vendor-without-npm
-vendor-without-npm: node-fallbacks runtime_js fallback_decoder bun_error mimalloc picohttp zlib boringssl libarchive lolhtml sqlite usockets uws lshpack tinycc c-ares zstd base64
+vendor-without-npm: node-fallbacks runtime_js fallback_decoder bun_error mimalloc picohttp zlib boringssl libarchive lolhtml sqlite usockets uws lshpack tinycc c-ares zstd
 
 
 .PHONY: vendor-without-check
diff --git a/bench/snippets/buffer-base64.mjs b/bench/snippets/buffer-base64.mjs
new file mode 100644
index 0000000000..96bab6f039
--- /dev/null
+++ b/bench/snippets/buffer-base64.mjs
@@ -0,0 +1,21 @@
+import { bench, run } from "./runner.mjs";
+
+function makeBenchmark(size, isToString) {
+  const base64Input = Buffer.alloc(size, "latin1").toString("base64");
+  const base64From = Buffer.from(base64Input, "base64");
+
+  if (!isToString)
+    bench(`Buffer.from(${size} bytes, 'base64')`, () => {
+      Buffer.from(base64Input, "base64");
+    });
+
+  if (isToString)
+    bench(`Buffer(${size}).toString('base64')`, () => {
+      base64From.toString("base64");
+    });
+}
+
+[32, 512, 64 * 1024, 512 * 1024, 1024 * 1024 * 8].forEach(s => makeBenchmark(s, true));
+[32, 512, 64 * 1024, 512 * 1024, 1024 * 1024 * 8].forEach(s => makeBenchmark(s, false));
+
+await run();
diff --git a/scripts/all-dependencies.ps1 b/scripts/all-dependencies.ps1
index f4426e4709..cc11006047 100644
--- a/scripts/all-dependencies.ps1
+++ b/scripts/all-dependencies.ps1
@@ -47,9 +47,6 @@ function Build-Dependency {
   $Script:DidAnything = $true
 }
 
-Build-Dependency `
-  -Script "base64" `
-  -Outputs @("base64.lib")
 Build-Dependency `
   -Script "boringssl" `
   -Outputs @("crypto.lib", "ssl.lib", "decrepit.lib")
diff --git a/scripts/all-dependencies.sh b/scripts/all-dependencies.sh
index 06bf35fc6c..70c576a67f 100755
--- a/scripts/all-dependencies.sh
+++ b/scripts/all-dependencies.sh
@@ -4,18 +4,18 @@ source "$(dirname -- "${BASH_SOURCE[0]}")/env.sh"
 FORCE=
 
 while getopts "f" opt; do
-  case ${opt} in
-    f )
-      FORCE=1
-      ;;
-    \? )
-      echo "Usage: all-dependencies.sh [-h] [-f]"
-      echo "Options:"
-      echo " h     Print this help message"
-      echo " f     Set force to 1"
-      exit 1
-      ;;
-  esac
+    case ${opt} in
+    f)
+        FORCE=1
+        ;;
+    \?)
+        echo "Usage: all-dependencies.sh [-h] [-f]"
+        echo "Options:"
+        echo " h     Print this help message"
+        echo " f     Set force to 1"
+        exit 1
+        ;;
+    esac
 done
 
 BUILT_ANY=0
@@ -52,7 +52,6 @@ dep() {
     BUILT_ANY=1
 }
 
-dep base64 libbase64.a
 dep boringssl libcrypto.a libssl.a libdecrepit.a
 dep cares libcares.a
 dep libarchive libarchive.a
diff --git a/scripts/build-base64.ps1 b/scripts/build-base64.ps1
deleted file mode 100644
index 91f5ed08cf..0000000000
--- a/scripts/build-base64.ps1
+++ /dev/null
@@ -1,16 +0,0 @@
-$ErrorActionPreference = 'Stop'  # Setting strict mode, similar to 'set -euo pipefail' in bash
-. (Join-Path $PSScriptRoot "env.ps1")
-
-Push-Location (Join-Path $BUN_DEPS_DIR 'base64')
-try {
-  Set-Location (mkdir -Force build)
-
-  Run cmake @CMAKE_FLAGS -DBASE64_WERROR=0 ..
-  Run cmake --build . --clean-first --config Release
-  
-  Copy-Item base64.lib $BUN_DEPS_OUT_DIR
-  Write-Host "-> base64.lib"
-}
-finally {
-  Pop-Location
-}
diff --git a/scripts/build-base64.sh b/scripts/build-base64.sh
deleted file mode 100755
index 160875f96e..0000000000
--- a/scripts/build-base64.sh
+++ /dev/null
@@ -1,14 +0,0 @@
-#!/usr/bin/env bash
-set -euxo pipefail
-source $(dirname -- "${BASH_SOURCE[0]}")/env.sh
-
-cd $BUN_DEPS_DIR/base64
-
-rm -rf build
-mkdir -p build
-cd build
-
-cmake "${CMAKE_FLAGS[@]}" .. -GNinja -B .
-ninja
-
-cp libbase64.a $BUN_DEPS_OUT_DIR/libbase64.a
diff --git a/src/base64/base64.zig b/src/base64/base64.zig
index 8a495c8775..76a5b635d7 100644
--- a/src/base64/base64.zig
+++ b/src/base64/base64.zig
@@ -1,27 +1,6 @@
 const std = @import("std");
 const bun = @import("root").bun;
 
-pub const DecodeResult = struct {
-    written: usize,
-    fail: bool = false,
-};
-
-pub const LibBase64 = struct {
-    pub const State = extern struct {
-        eof: c_int,
-        bytes: c_int,
-        flags: c_int,
-        carry: u8,
-    };
-    pub extern fn base64_encode(src: [*]const u8, srclen: usize, out: [*]u8, outlen: *usize, flags: c_int) void;
-    pub extern fn base64_stream_encode_init(state: *State, flags: c_int) void;
-    pub extern fn base64_stream_encode(state: *State, src: [*]const u8, srclen: usize, out: [*]u8, outlen: *usize) void;
-    pub extern fn base64_stream_encode_final(state: *State, out: [*]u8, outlen: *usize) void;
-    pub extern fn base64_decode(src: [*]const u8, srclen: usize, out: [*]u8, outlen: *usize, flags: c_int) c_int;
-    pub extern fn base64_stream_decode_init(state: *State, flags: c_int) void;
-    pub extern fn base64_stream_decode(state: *State, src: [*]const u8, srclen: usize, out: [*]u8, outlen: *usize) c_int;
-};
-
 const mixed_decoder = brk: {
     var decoder = zig_base64.standard.decoderWithIgnore("\xff \t\r\n" ++ [_]u8{
         std.ascii.control_code.vt,
@@ -35,21 +14,28 @@ const mixed_decoder = brk: {
     break :brk decoder;
 };
 
-pub fn decode(destination: []u8, source: []const u8) DecodeResult {
-    var wrote: usize = 0;
-    mixed_decoder.decode(destination, source, &wrote) catch {
-        return .{
-            .written = wrote,
-            .fail = true,
+pub fn decode(destination: []u8, source: []const u8) bun.simdutf.SIMDUTFResult {
+    const result = bun.simdutf.base64.decode(source, destination, false);
+
+    if (!result.isSuccessful()) {
+        // The input does not follow the WHATWG forgiving-base64 specification
+        // https://infra.spec.whatwg.org/#forgiving-base64-decode
+        // https://github.com/nodejs/node/blob/2eff28fb7a93d3f672f80b582f664a7c701569fb/src/string_bytes.cc#L359
+        var wrote: usize = 0;
+        mixed_decoder.decode(destination, source, &wrote) catch {
+            return .{
+                .count = wrote,
+                .status = .invalid_base64_character,
+            };
         };
-    };
-    return .{ .written = wrote, .fail = false };
+        return .{ .count = wrote, .status = .success };
+    }
+
+    return result;
 }
 
 pub fn encode(destination: []u8, source: []const u8) usize {
-    var outlen: usize = destination.len;
-    LibBase64.base64_encode(source.ptr, source.len, destination.ptr, &outlen, 0);
-    return outlen;
+    return bun.simdutf.base64.encode(source, destination, false);
 }
 
 pub fn decodeLenUpperBound(len: usize) usize {
diff --git a/src/bun.js/bindings/bun-simdutf.cpp b/src/bun.js/bindings/bun-simdutf.cpp
index d02ff98543..4909be19aa 100644
--- a/src/bun.js/bindings/bun-simdutf.cpp
+++ b/src/bun.js/bindings/bun-simdutf.cpp
@@ -324,4 +324,33 @@ size_t simdutf__utf32_length_from_utf8(const char* input, size_t length)
 {
     return simdutf::utf32_length_from_utf8(input, length);
 }
+
+size_t simdutf__base64_encode(const char* input, size_t length, char* output, int is_urlsafe)
+{
+    return simdutf::binary_to_base64(input, length, output, is_urlsafe ? simdutf::base64_url : simdutf::base64_default);
+}
+
+SIMDUTFResult simdutf__base64_decode_from_binary(const char* input, size_t length, char* output, size_t outlen_, int is_urlsafe)
+{
+    size_t outlen = outlen_;
+    auto res = simdutf::base64_to_binary_safe(input, length, output, outlen, is_urlsafe ? simdutf::base64_url : simdutf::base64_default);
+
+    if (res.error == simdutf::error_code::SUCCESS) {
+        return { .error = 0, .count = outlen };
+    }
+
+    return { .error = res.error, .count = res.count };
+}
+
+SIMDUTFResult simdutf__base64_decode_from_binary16(const char16_t* input, size_t length, char* output, size_t outlen_, int is_urlsafe)
+{
+    size_t outlen = outlen_;
+    auto res = simdutf::base64_to_binary_safe(input, length, output, outlen, is_urlsafe ? simdutf::base64_url : simdutf::base64_default);
+
+    if (res.error == simdutf::error_code::SUCCESS) {
+        return { .error = 0, .count = outlen };
+    }
+
+    return { .error = res.error, .count = res.count };
+}
 }
\ No newline at end of file
diff --git a/src/bun.js/bindings/bun-simdutf.zig b/src/bun.js/bindings/bun-simdutf.zig
index f7ab8b21db..98f426cd76 100644
--- a/src/bun.js/bindings/bun-simdutf.zig
+++ b/src/bun.js/bindings/bun-simdutf.zig
@@ -5,6 +5,10 @@ pub const SIMDUTFResult = extern struct {
     status: Status,
     count: usize = 0,
 
+    pub fn isSuccessful(this: *const SIMDUTFResult) bool {
+        return this.status == Status.success;
+    }
+
     pub const Status = enum(i32) {
         success = 0,
         /// Any byte must have fewer than 5 header bits.
@@ -364,3 +368,21 @@ pub const trim = struct {
         return buf[0..utf8_len(buf)];
     }
 };
+
+pub const base64 = struct {
+    extern fn simdutf__base64_encode(input: [*]const u8, length: usize, output: [*]u8, is_urlsafe: c_int) usize;
+    extern fn simdutf__base64_decode_from_binary(input: [*]const u8, length: usize, output: [*]u8, outlen: usize, is_urlsafe: c_int) SIMDUTFResult;
+    extern fn simdutf__base64_decode_from_binary16(input: [*]const u16, length: usize, output: [*]u8, outlen: usize, is_urlsafe: c_int) SIMDUTFResult;
+
+    pub fn encode(input: []const u8, output: []u8, is_urlsafe: bool) usize {
+        return simdutf__base64_encode(input.ptr, input.len, output.ptr, @intFromBool(is_urlsafe));
+    }
+
+    pub fn decode(input: []const u8, output: []u8, is_urlsafe: bool) SIMDUTFResult {
+        return simdutf__base64_decode_from_binary(input.ptr, input.len, output.ptr, output.len, @intFromBool(is_urlsafe));
+    }
+
+    pub fn decode16(input: []const u16, output: []u8, is_urlsafe: bool) SIMDUTFResult {
+        return simdutf__base64_decode_from_binary16(input.ptr, input.len, output.ptr, output.len, @intFromBool(is_urlsafe));
+    }
+};
diff --git a/src/bun.js/webcore/encoding.zig b/src/bun.js/webcore/encoding.zig
index f24dfbf8f0..8156ca0f7e 100644
--- a/src/bun.js/webcore/encoding.zig
+++ b/src/bun.js/webcore/encoding.zig
@@ -1089,7 +1089,7 @@ pub const Encoder = struct {
             },
 
             .base64, .base64url => {
-                return bun.base64.decode(to_ptr[0..to_len], input[0..len]).written;
+                return bun.base64.decode(to_ptr[0..to_len], input[0..len]).count;
             },
         }
     }
@@ -1261,7 +1261,7 @@ pub const Encoder = struct {
                 const outlen = bun.base64.decodeLen(slice);
                 const to = allocator.alloc(u8, outlen) catch return &[_]u8{};
 
-                const wrote = bun.base64.decode(to[0..outlen], slice).written;
+                const wrote = bun.base64.decode(to[0..outlen], slice).count;
                 return to[0..wrote];
             },
         }
diff --git a/src/deps/base64 b/src/deps/base64
deleted file mode 160000
index 3a5add8652..0000000000
--- a/src/deps/base64
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 3a5add8652076612a8407627a42c768736a4263f
diff --git a/src/resolver/data_url.zig b/src/resolver/data_url.zig
index 002044ce69..177337fc96 100644
--- a/src/resolver/data_url.zig
+++ b/src/resolver/data_url.zig
@@ -122,7 +122,7 @@ pub const DataURL = struct {
             const len = bun.base64.decodeLen(percent_decoded);
             const buf = try allocator.alloc(u8, len);
             const result = bun.base64.decode(buf, percent_decoded);
-            if (result.fail or result.written != len) {
+            if (!result.isSuccessful() or result.count != len) {
                 return error.Base64DecodeError;
             }
             return buf;
diff --git a/src/sourcemap/sourcemap.zig b/src/sourcemap/sourcemap.zig
index 19f7d20917..6f4855fac9 100644
--- a/src/sourcemap/sourcemap.zig
+++ b/src/sourcemap/sourcemap.zig
@@ -86,10 +86,10 @@ pub fn parseUrl(
                     const len = bun.base64.decodeLen(base64_data);
                     const bytes = arena.alloc(u8, len) catch bun.outOfMemory();
                     const decoded = bun.base64.decode(bytes, base64_data);
-                    if (decoded.fail) {
+                    if (!decoded.isSuccessful()) {
                         return error.InvalidBase64;
                     }
-                    break :json_bytes bytes[0..decoded.written];
+                    break :json_bytes bytes[0..decoded.count];
                 },
                 ',' => break :json_bytes source[data_prefix.len + 1 ..],
                 else => break :try_data_url,