Custom Emojis
Public-safe notes about custom emojis on Mastodon and other Fediverse platforms.
Custom emojis help give an instance personality and make posts more expressive.
What are custom emojis?
Custom emojis are small images uploaded to an instance.
They can be used in posts, profiles, display names, and reactions depending on the platform.
Example emoji shortcode:
- :cat_wave:
Example in a sentence:
- Good morning! :cat_wave:
Why custom emojis are useful
Custom emojis can help create:
- instance identity
- community culture
- inside jokes
- cute reactions
- seasonal decorations
- project branding
- mascot expressions
They make an instance feel more personal.
Common emoji types
Good custom emoji categories:
- greetings
- reactions
- moods
- mascot faces
- seasonal emojis
- admin/status emojis
- hobby emojis
- server identity emojis
Examples:
- :hello:
- :wave:
- :boost:
- :coffee:
- :linux:
- :cat:
- :happy:
- :sleepy:
Good emoji design
Good custom emojis should be:
- simple
- readable at small size
- high contrast
- clean outline
- not too detailed
- transparent background if possible
- consistent style
Remember: emojis are usually shown very small.
If the design has too many details, it may become unreadable.
File format
Common formats:
- PNG
- WEBP
- GIF
Use PNG or WEBP for static emojis.
Use GIF or animated WEBP only if the platform supports it.
Size
Keep emojis small and optimized.
Good idea:
- square format
- transparent background
- simple shape
- clear expression
- small file size
Avoid very large files.
Naming custom emojis
Emoji names should be short and clear.
Good names:
- :cat_wave:
- :linux_penguin:
- :coffee:
- :error404:
- :happy_blob:
Avoid names that are too long or confusing.
Use lowercase names with underscores.
Mascot emojis
If an instance has a mascot, create multiple expressions.
Examples:
- :mascot_wave:
- :mascot_happy:
- :mascot_sad:
- :mascot_thinking:
- :mascot_party:
- :mascot_sleepy:
- :mascot_boost:
- :mascot_love:
This gives the instance a consistent visual identity.
Animated emojis
Animated emojis can be fun, but use them carefully.
Good animation:
- small movement
- short loop
- not too fast
- not flashing
- not distracting
Avoid:
- rapid flashing
- large movement
- high brightness flashing
- huge file size
Accessibility matters.
Importing emoji packs
Some Mastodon instances allow admins to import emoji packs.
Before importing:
- check license
- check file size
- check naming
- check if emojis are appropriate
- check if they match instance rules
Do not upload copyrighted or stolen artwork without permission.
Emoji moderation
Custom emojis should still follow instance rules.
Avoid emojis that include:
- hate symbols
- harassment
- private user data
- copyrighted logos without permission
- sexual content if not allowed
- violent or extremist symbols
- confusing impersonation
Useful emoji ideas
General reaction set:
- :yes:
- :no:
- :thanks:
- :welcome:
- :boost:
- :party:
- :hug:
- :thinking:
- :sad:
- :angry:
- :sleepy:
Tech/Linux set:
- :linux:
- :terminal:
- :server:
- :docker:
- :bug:
- :fixed:
- :backup:
- :coffee:
Community set:
- :wave:
- :heart:
- :good_morning:
- :good_night:
- :welcome_new_user: