When comparing Iosevka vs Bitstream DejaVu Sans Mono, the Slant community recommends Iosevka for most people. In the question“What are the best programming fonts?” Iosevka is ranked 6th while Bitstream DejaVu Sans Mono is ranked 13th. The most important reason people chose Iosevka is:
Iosevka is very clear and legible on all displays and in all sizes.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Readable
Iosevka is very clear and legible on all displays and in all sizes.
Pro Narrow
Narrow character width uses horizontal screen space more efficiently.
Pro Large number of weights
This font comes in seven different weights, ranging from thin and extra-light to heavy.
Pro Great customizability
There is full customization of styles and variants in Iosevka.
Pro Support for Cyrillic and Greek letters
Iosevka is quite flexible in that it supports Cyrillic and Greek letters.
Pro Free and open source
Iosevka is free and open source.
Pro Powerline support
Includes characters for supporting Powerline/Airline for terminals and terminal editors.
Pro Ligature characters look great
Few fonts have a good ligation feature. Ligature characters (such as æ or the German ß) are supported in Iosevka and look just as you'd expect them to.
Pro Several styles available
Many of the common styles are available, including Sans Serif and Slab Serif with normal, bold, italic, and bold italic styles.
Pro IPA Support
IPA is a system containing the sounds of spoken language and includes speech qualities such as intonation.
Pro Easy on user's eyes
Due to it being readable on all types of displays, Iosevka isn't hard on the user's eyes.
Pro Well-maintained
The developer is active and responds to user questions and issues.
Pro Good CJK compatibility
Iosevka integrates CJK characters well, those being characters of the Chinese, Japanese, Korean, and occasionally Vietnamese languages.
Pro Also variant with tiny serifs available ("Slab")
For better reading longer texts.
Pro Very clear distinction between similar characters
It's easy to distinguish between characters such as I, 1, l, O, and 0 in DejaVu Sans Mono.
Pro Clean, readable design
Reading the text is pleasant and effortless. Letter forms combine nicely into words.
Pro It's subtle, yet stylish and extremely readable, very easy on eyes and very effective for long development sessions
Pro Nice uniform spacing
The font is well spaced and doesn't break up words.
Pro Excellent unicode support
DejaVu Sans Mono has one of the most complete Unicode fonts available. This means you have access to a wide range of special symbols including mathematical symbols like arrows, operators, and special alphabets. This is useful for certain languages that require special characters like Agda.
Some languages allow using these characters optionally. There are editor modes that display characters like this without changing the underlying file, much like syntax highlighting. The Emacs modes for OCaml and Haskell are prime examples.
Pro Available with every linux distribution and works fine in vim, emacs and atom
It's also included in modern versions of Windows.
Pro Bold font is the same width as the regular weight font
The Sans Mono version is graphically close to Andale Mono (Microsoft core web font), slightly bolder, with the added bonus of the bold font being the same width as the regular one (unlike Andale Mono). It is a nice property with some syntax highlighting text editors.
Pro Closely related to MobaFont
For MobaXterm users, this font closely mirrors the embedded MobaFont so they can use a monospace font across other applications.
Cons
Con Too narrow
Con Must do a custom build to get all ligatures
Con Fewer ligatures than other fonts
Iosevka has a nice ligation set, but it doesn't have as many ligatures as fonts like Hasklig, Monoid, or Pragmata Pro.
Con Crowded bold styles
At size 12, in bold text, some letters bump up against each other too closely, greatly reducing legibility.
Con Tilde character lacks curvature
The tilde character in this font ('~') does not have enough curvature to be read easily at small sizes. This can be a concern for Unix(-like) shell users and script writers, as the tilde is used relatively often compared to other symbols.
Con The "-" symbol is short
For example, when using the '-' symbol for borders, it's super short in this font.
Con No ligatures
Missing programming ligatures.
Con Dotted zero
Dotted zero is less readable than slashed zero.
Con Not suitable for Vietnamese
This font is really ugly when used with Vietnamese characters.
Con Missing some Vietnamese characters
ấ, ề, ự, etc. are missing in DejaVu Sans Mono.
Con Some characters are similar
Small 'L', capital 'i' and 1 are too similar.
Con Too much serif on lowercase L
Lowercase L has a top left serif and a bottom right curved serif, and both are too long; so long that they make lowercase L look like an uppercase i.