Beware when base64-encoding on the CLI using echo

Recently I needed to base64-encode a string. To do this I turned to the CLI and piped the output of echo to base64.

# Don't use! Correct command further down this post.
$ echo 'test' | base64

Although the output looks quite good, things didn’t quite work out when using the string: it failed when used in an implementation.

Tracking down the issue I worked my way back and decided to double check the base64-encoded string (dGVzdAo=) for its correctness. Using PHP I re-encoded the input and voila:

$ php -r "echo base64_encode('test');"

That’s different output … and it’s also to correct result. But how come? Is base64 on the CLI wrong?


Don’t worry, base64 on the CLI works fine. The problem we’re having here is further upstream, namely with the use of echo. By default echo will append a newline to its output, and that’s why base64 is returning an unexpected result.

Thankfully echo has a -n switch to suppress the trailing newline. By using that, things work as expected:

# Add -n to echo to prevent it from adding a newline
$ echo -n 'test' | base64

Let this post act as a note to my future self … πŸ˜…


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AV1, the video codec of the future

Next to praising the AV1 Codec and providing conversion examples (using ffmpeg), Andrey Sitnik also gives a good overview on containers and codecs – concepts every web developer who embed video should know imho – in his post on the subject:

File extensions for video (.mp4, .wmv, .webm or .mov) barely represent containers. When you see a .mp4 extension, the only thing you can be sure about is that the MP4 container had been used to package a file. The choice of codec depends entirely on a creator: it can be H.264/AAC, or AV1/Opus, or something else.

Better web video with AV1 codec →

Text Escaping and Unescaping in JavaScript with strutil

Today the package strutil came in handy, after receiving (*) this UTF-8 Quoted Printable text in my hands:


Thanks to strutil#unescapeFromMime() I was able to regain the original string:

Test πŸ‘»

Upon further investigation of strutil it turns out that this package is really powerful as it can do a truckload of things when it comes to encoding:

Text Escaping and Unescaping in JavaScript (UTF-8, UTF-16, UTF-32, dec, hex, punycode, mime, base64, and more)

jsescape demo →

(*) The encoding in the first place itself happened automatically by Amazon, whilst storing User-Defined Metadata on an S3 Object:

User-defined metadata is a set of key-value pairs. Amazon S3 stores user-defined metadata keys in lowercase. Each key-value pair must conform to US-ASCII when using REST and UTF-8 when using SOAP or browser-based uploads via POST.

Now you know πŸ˜‰