Is it bad to store many files in a single folder?

No the depth of your directory structure has almost no impact to load time.

Maybe if your structure is very depth and the URLs for the images are very long you can hit the maximum length or your markup blows up. But a flat hierarchy should not be a problem as long as you keep the file names short enough.

Then again, if your store everything in one directory, there may be name collisions. But WordPress checks for that during the upload with wp_unique_filename(), so you should not worry about that too.

Related Posts:

  1. Creating directory in uploads – wp_mkdir_p() or WP_Filesystem?
  2. Convenient way to use wp_filesystem
  3. Is there a WP Way of getting a filehandle?
  4. Is fopen() forbidden in WP?
  5. Converting fopen/fwrite operations to WP_filesystem
  6. External pages redirecting back to wordpress
  7. WordPress Login doesnt respond after using Filezilla to upload my files on the server
  8. List of files/folders writable by the web server?
  9. Save PDF File From Plugin to Filesystem /wp_upload
  10. accessing files in custom folder in wordpress
  11. What dependencies should I load and to use the WP_Filesystem?
  12. What files are safe to delete after a security breach in WP content folder?
  13. Failed opening required
  14. Correct file permissions for in-browser updates using WP-CLI
  15. WordPress installation on digitalocean eating the server storage
  16. Serve contents from Nextcloud / WebDAV
  17. temphangle variable missing when using wp_filesystem copy
  18. File ownership for file tree php user ID – Folder permission 775
  19. How to write to a text file and save it in a folder for later download?
  20. 403 Error on “/”
  21. Get names and paths from unzip_file()
  22. Should I use Filesystem API for reading files or listing directories?
  23. saving file to external server vip
  24. Time limited file download upon form submit
  25. Does unzip_file() over-write by default?
  26. What’s the best way to dedupe a table?
  27. What are the best practices for using a caching plugin on a shared host?
  28. Optimize apache for WP use
  29. What’s the difference between wp_insert_user() and wp_create_user()
  30. How to fix wordpress slow first time load (Local Server)?
  31. How to convert the file path to a URL of the same file?
  32. Any reason why wp_cache_set not to work?
  33. In terms of performance – Is unmanaged VPS better than a managed one – for WP sites?
  34. How can WordPress be made more memory efficient?
  35. WordPress speed slow after .5 million single image post via wp-cli
  36. Defer Code in Widgets – Page Speed
  37. Is there any performance consideration when using Custom Post Types?
  38. Universal problem: first request after ~25 second inactivity always slower (~1 second) than subsequent requests (~1/10sec)
  39. Relationship between performance and database size
  40. Changing BIGINT to INT
  41. WordPress website loads but is not displayed until page scrolled
  42. How to move WordPress theme files into a subfolder without breaking the theme?
  43. How do I maintain static directories on multisite subdomains?
  44. How much will mounting wp-content on a separate NFS server impact performance?
  45. Image Preloading
  46. WP_Query times out
  47. How to check if txt file exists inside template folder?
  48. WordPress Scalability – One Instance or Several?
  49. Looking for most performant way to execute several similar WP queries within shortcodes
  50. It is a good idea to store values from the global $post if they are used multiple times?
  51. Relative links for performance?
  52. cross-host benchmarking with wordpress
  53. Performance problem with first load
  54. Does registering multiple shortcodes impact performance?
  55. Correct way to perform non-cacheable DB query
  56. Reasonable Size Limit to options entry
  57. Improve performance by removing unnecessary database queries
  58. Is it possible to make WordPress PHP faster through caching or compiling it?
  59. W3 Total Cache: use cache for request with ignorable query string [closed]
  60. Running WordPress as FTP user?
  61. How to analyze wordpress plugin performance
  62. how to use shortinit in wordpress
  63. use of 10 new WP_Query : loading too slow (with url) [closed]
  64. Optimizing site speed by localizing paths
  65. How to replace file_get_contents() with a WordPress Filesystem call
  66. Namespaced shortcode?
  67. How to combine multiple wp_insert_post into one in order to gain better performance
  68. Is it better to store images and other files in the root directory or the theme directory
  69. How to optimize on-the-fly theme switching for mobile browsers?
  70. Theme, WordPress Version, MySQL Version, PHP Version Update affected files and folders
  71. Does WordPress create a new Linux user when creating a new WordPress blog?
  72. Last-Modified header support doesn’t speed up server processing – want more
  73. Look for a file in a theme before loading from plugin
  74. Why does Thickbox jQuery load on my site?
  75. get_template_directory() returns wrong address on VPS
  76. Performance testing a WordPress site locally?
  77. How do I serve fully cached full HTML on cloudfront
  78. Page load timer?
  79. Pages section (only) not loading after publishing large number of pages
  80. How do you make a site load faster when offloading is not an option?
  81. how to embed Pdf and Video Without effecting page speed?
  82. Save media files (images) to database instead of the filesystem
  83. WordPress is very slow, even it’s not opening sometimes
  84. Regular XML-RPC timeouts
  85. Best way to store 1 billion+ posts?
  86. Optimize WP site for millions of posts
  87. Change loading order of blocks
  88. Can’t Install WordPress (local) Failed to open file wp-includes/wp-db.php
  89. Avoid ‘uploads’ 777 permissions: Potential threat or clean solution?
  90. Why WordPress takes time to make request to save post?
  91. Fatal error: Allowed memory size of bytes exhausted (tried to allocate 36 bytes)
  92. Custom Post Type vs Shortcode: Which one is more performant?
  93. Post OrderBy slow performance
  94. How to handle high load of traffic of my server
  95. Using tag or inline style attribute?
  96. WordPress and TTFB (time to first byte) stats
  97. What’s a good tool for speed benchmarking? [closed]
  98. How do I upload my WordPress code files from previous website onto local host WordPress website?
  99. Can running a WP-Cron to update_post_meta cause performance issues?
  100. Hook on opening a media/document