Shiny Pokémon are extremely rare Pokémon that differ in coloration from their regular appearance. These color variations may range from minor hue adjustments to completely altered palettes. Only one shiny variation exists for each Pokémon.
In the Map View and Sightings view, Shiny Pokémon are shown in their regular coloration until they appear on the encounter screen or on the summary page, where they have an aura of stars around them, a shiny tab shown above the CP and their different coloration is visible.
The in-game RNG determines if wild-spawned and Raid Pokémon are Shiny for each player's instance separately; thus a Shiny Pokémon from the same spawn point may not, and most likely will not, appear shiny to other Trainers.
Once a player captures 10 Shiny (non-Shadow) Pokémon, they will unlock the Shiny Pokédex so they can see each entry of Shiny Pokémon they have seen/caught. Shiny Shadow Pokémon are registered to the Shadow Pokédex, which has additional switch buttons for shiny forms for eligible Pokédex entries.
Odds of a Shiny Pokémon
According to the latest research conducted by TheSilphRoad, there are several likely categories that determine the odds of a Pokémon being Shiny.
Note: the following numbers are from their most recent estimates.
- Base rate: 1/512-500 (0.2%)
- Medium Event: 1/128-125 (0.8%)
- Permaboost: 1/64-62.5 (1.6%)
- Raid/Egg (if different from Permaboost): 1/56.9-1/50 (2%)
- Community Day: 1/25.6-1/25 (4%)
- Legendary Raid: 1/20.48-1/20 (5%)
- Raid Event: 1/10.24-1/10 (10%)
List of Shiny Pokémon
Almost all Shiny forms of Pokémon are currently in game assets, but only part of them are currently available to obtain by players in the gameplay.
- For list of Shiny Pokémon that are available in the game, see here: List of Shiny Pokémon
- For list of Shiny Pokémon by their release dates, see here: List of Shiny Pokémon release dates
- For comparison of regular and shiny sprites of Pokémon, see here: List of Shiny Pokémon comparison
List of Shiny Pokémon with limited-time availability
Some Pokémon can only be obtained in their Shiny form for a limited time, after which they cannot be obtained again until either a new event occurs or they are made permanently available.
- Mew can currently only be obtained in its Shiny form as the final reward for the Special Research All-in-One #151, which required a purchase from Pokémon GO Tour: Kanto.
- Unown can only be obtained in its Shiny form during limited time periods. See Unown article for time periods details.
- Smeargle was only available during the New Pokémon Snap Celebration.
- Meltan, and by extension Melmetal, can only be obtained in its Shiny form (both in the wild or from Research Tasks) during limited time periods. See Meltan article for time periods details.
All Shiny Shadow/Purified Pokémon falls in this category, as they can only be obtained as the reward from defeating a Team GO Rocket Leader or Jessie and James (not Giovanni or any Grunts) and the Leaders' teams change every few months (or in the case of Jessie/James they simply stop being available), making obtaining that particular form unobtainable for the time being.
Most Costume Pokémon are in this category as well due to being available only during certain time-limited events (which may or may not ever come back)
- There is one exception: the Libre Pikachu, which is a Rank 24 reward in the Go Battle League.
- Normally, evolved stages of Pokémon cannot be shiny in the encounter screen, including Pokémon evolved from Baby Pokémon (except Pikachu, Chansey, Mr. Mime and Roselia). As a result, evolved shiny Pokémon can only obtained by evolution.
- Since 2020, many evolved forms of Baby Pokémon have become shiny catchable after certain events, including:
- Magmar in Lunar New Year 2020;
- Sudowoodo in Tricky Pokémon 2020;
- Marill in Spring Event;
- Wobbuffet in its Pokémon Spotlight Hour;
- Clefairy in Summer Solstice;
- Jigglypuff in Pokémon GO Fest 2020;
- Electabuzz in its Community Day;
- Jynx in Holiday 2020;
- Hitmonlee, Hitmonchan, and Snorlax in Pokémon GO Tour: Kanto.
- Final evolution stages can be also be shiny since their Mega Evolution release.
- Shiny Pokémon cannot be batch-transferred, and Trainers will be notified if they try to transfer them.
- Shiny Pokémon remain shiny after being evolved.
- Also Pokémon cannot become shiny via evolving a non-shiny one.
- Unlike the case with seeing regular Pokémon in the Gym, seeing Shiny Pokémon in the Gym for the first time, before capturing them, won't unlock the Pokémon's shiny form switches in the Pokédex summary page.
- There are also no file assets for form switches of only-seen Shiny Pokémon in the Pokédex.
- Registering a shiny Pokémon will also register the non-shiny form to the Pokédex, if the Pokémon was not previously registered.
- Shiny Legendary Pokémon have a 100% catch rate in Raid Battles (unless a certain GPS error occurs), but remain the same catch rate in Research Breakthrough.
- Sableye, Mawile, Absol, Budew, Roserade, Honchkrow, Electivire, Magmortar, Togekiss, Dusknoir, Mamoswine, Magnezone, Leafeon, Glaceon, Mime Jr., Sylveon and the evolution lines of Snorunt, Aron, Swablu, Shinx, Drifloon, Clamperl, Patrat, Lillipup, Klink, Yamask and Minccino are the only Pokémon to have both regular and shiny forms released at the same time.
- In the main Pokémon series, Gold and Silver were the first games to introduce shiny Pokémon.
- Along with releases of new Legendary Raid Bosses in 2017, assets for shiny forms of these Legendary Pokémon are also added to the game.
- Shiny Zapdos was temporally available from Raid Battle in 2017 due to game creators' mistake.
- During the Halloween event in 2017, there were shiny forms of Gastly family members added to game data, although they weren't released to be caught in gameplay. 
- Along with each release of selected Pokémon from the Hoenn region, there are added to game data all of the sprites for shiny forms of that region's respective Pokémon. 
- Since then, the shiny sprites from later regions have been added to the game with their normal versions.
- Between April 7th and 10th, players started noticing that 2D sprites of Kanto- and Johto-region Pokémon had changed, thus they started speculating that during the Kanto Celebration 2018 event some or even more of shiny variants of these Kanto Pokémon might be released. 
- Moreover, Reddit user u/Chrales through the data-mining found and revealed that, in fact, plenty of 2D sprites for shiny variants of Kanto and Johto Pokémon had been added to the game server. However, none of these Shiny Pokémon had their in-game 3D models added by that time. 
- Despite all of these 2D sprites of Shiny Pokémon being added to the game, none of the Pokémon had their shiny variants released during the Kanto Celebration event.
- On each Community Day, there is a significantly higher chance to encounter a shiny form of featured Pokémon that generally spawns more often during this event.
- Research estimates that there was a 1 in 22.7 chance of capturing a shiny Pikachu during the first Community Day.
- Shiny Shuckle became available for a short period of time before the start of the Pokémon GO Safari Zone Sentosa.
- Unlike all other Pokémon, it is impossible to tell in advance if a wild-caught Ditto may be Shiny or not as it is not revealed until after the disguise is removed after catching. (Due to Ditto being unable to mimic a Pokémon in their Shiny form in the wild but still having a chance to be Shiny.) This does not apply to a Ditto obtained as a Reward, as it will not be transformed on the catch screen.
- Gastly family shiny 3D assets. "/r/TheSilphRoad."
- gen3 sprites with all shinies !/r/TheSilphRoad. Retrieved 2017-12-11.
- It seems a decent amount of the sprites have changed shades of color. /r/TheSilphRoad. Retrieved on 2018-04-20.
- u/Chrales all gen1 and gen2 new shiny pokémon added. /r/TheSilphRoad. Retrieved on 2018-04-20.
- Estimating Community Day's Boosted Shiny Rate. /r/TheSilphRoad. Retrieved on 2018-02-25.
- Shiny Shuckle leaked early?. /r/TheSilphRoad. Retrieved on 2019-04-18.