{"id":"backups.why-does-the-backup-time-left-keep-changing","url":"/faq/backups/why-does-the-backup-time-left-keep-changing","category":{"id":"backups","title":"Backups & restore points"},"subcategory":{"id":"speed-progress","title":"Speed, progress and the first backup"},"question":"Why does the backup's time remaining keep changing?","alt_questions":["backup ETA jumps around","time left wrong on backup","estimate keeps going up","backup estimate inaccurate"],"short_answer":"The estimate follows the real transfer speed, which varies with file sizes, the cloud service and how busy your Mac is. Idle stalls are excluded, so it settles as the backup goes on.","answer_markdown":"Because it's worked out from the speed the backup is actually achieving, and that changes. Lots of small files move more slowly than a few big ones, cloud services vary through the day, and Storage Studio slows itself down when you're using the Mac heavily.\n\nStalls don't distort it: time when nothing was moving is excluded from the estimate and shown separately as idle. Over a long backup the figure settles as it gets more to go on.","answer_html":"<p>Because it&#39;s worked out from the speed the backup is actually achieving, and that changes. Lots of small files move more slowly than a few big ones, cloud services vary through the day, and Storage Studio slows itself down when you&#39;re using the Mac heavily.</p>\n<p>Stalls don&#39;t distort it: time when nothing was moving is excluded from the estimate and shown separately as idle. Over a long backup the figure settles as it gets more to go on.</p>","answer_text":"Because it's worked out from the speed the backup is actually achieving, and that changes. Lots of small files move more slowly than a few big ones, cloud services vary through the day, and Storage Studio slows itself down when you're using the Mac heavily.\n\nStalls don't distort it: time when nothing was moving is excluded from the estimate and shown separately as idle. Over a long backup the figure settles as it gets more to go on.","tags":["eta","progress"],"related":[{"id":"backups.how-do-i-read-backup-progress","question":"How do I read the progress on a running backup?","url":"/faq/backups/how-do-i-read-backup-progress"}],"applies_to":"all","last_reviewed":"2026-10-01","title":"Why does the backup's time remaining keep changing? — Storage Studio FAQ","description":"The estimate follows the real transfer speed, which varies with file sizes, the cloud service and how busy your Mac is. Idle stalls are excluded, so it settles as the backup goes on.","crumbs":[{"name":"Home","path":"/"},{"name":"FAQ","path":"/faq/"},{"name":"Backups & restore points","path":"/faq/backups/"},{"name":"Why does the backup's time remaining keep changing?","path":"/faq/backups/why-does-the-backup-time-left-keep-changing"}],"jsonld":{"@context":"https://schema.org","@type":"FAQPage","url":"https://storagestudio.us/faq/backups/why-does-the-backup-time-left-keep-changing","inLanguage":"en","dateModified":"2026-10-01","mainEntity":[{"@type":"Question","name":"Why does the backup's time remaining keep changing?","alternateName":["backup ETA jumps around","time left wrong on backup","estimate keeps going up","backup estimate inaccurate"],"acceptedAnswer":{"@type":"Answer","text":"Because it's worked out from the speed the backup is actually achieving, and that changes. Lots of small files move more slowly than a few big ones, cloud services vary through the day, and Storage Studio slows itself down when you're using the Mac heavily.\n\nStalls don't distort it: time when nothing was moving is excluded from the estimate and shown separately as idle. Over a long backup the figure settles as it gets more to go on.","url":"https://storagestudio.us/faq/backups/why-does-the-backup-time-left-keep-changing"}}]},"fragment":"<div class=\"wrap fl-wrap\"><div class=\"fl-layout\"><aside class=\"fl-side\" aria-label=\"FAQ topics\"><details open><summary>All topics</summary><ul class=\"fl-tree\"><li><a href=\"/faq/getting-started/\">Getting started</a> <span>70</span></li><li><a href=\"/faq/freeing-space/\">Freeing up space</a> <span>182</span></li><li><a href=\"/faq/moving-folders/\">Moving folders</a> <span>144</span></li><li><a href=\"/faq/apps/\">Apps</a> <span>146</span></li><li><a href=\"/faq/external-drives/\">External drives</a> <span>169</span></li><li><a href=\"/faq/finder-location/\">Finding things in Finder</a> <span>70</span></li><li><a href=\"/faq/cloud-accounts/\">Cloud accounts</a> <span>158</span></li><li><a href=\"/faq/icloud/\">iCloud &amp; iCloud Photos</a> <span>168</span></li><li><a href=\"/faq/data-transfers/\">Data Transfers</a> <span>119</span></li><li class=\"fl-open\"><a href=\"/faq/backups/\" aria-current=\"true\">Backups &amp; restore points</a> <span>126</span><ul><li><a href=\"/faq/backups/#data-backup-basics\">Data Backup basics</a> <span>15</span></li><li><a href=\"/faq/backups/#destinations\">Where backups go</a> <span>13</span></li><li><a href=\"/faq/backups/#encryption-passphrase\">Encryption and passphrases</a> <span>15</span></li><li><a href=\"/faq/backups/#scheduling\">When backups run</a> <span>16</span></li><li class=\"fl-on\"><a href=\"/faq/backups/#speed-progress\">Speed, progress and the first backup</a> <span>14</span></li><li><a href=\"/faq/backups/#versions-restore\">Versions and restoring</a> <span>11</span></li><li><a href=\"/faq/backups/#status-problems\">Status and problems</a> <span>12</span></li><li><a href=\"/faq/backups/#managing-sets\">Managing backup sets and destinations</a> <span>5</span></li><li><a href=\"/faq/backups/#backup-strategy\">Time Machine and backup strategy</a> <span>12</span></li><li><a href=\"/faq/backups/#restore-points\">Restore Points</a> <span>10</span></li><li><a href=\"/faq/backups/#self-backup\">Storage Studio&#39;s own settings backup</a> <span>3</span></li></ul></li><li><a href=\"/faq/delta-drive/\">Delta Drive, Delta Trust &amp; My Drive</a> <span>125</span></li><li><a href=\"/faq/bridge-devices/\">Bridge &amp; your devices</a> <span>111</span></li><li><a href=\"/faq/duplicates/\">Duplicate files</a> <span>74</span></li><li><a href=\"/faq/junk-yard/\">Junk Yard</a> <span>113</span></li><li><a href=\"/faq/tuhi-assistant/\">Tuhi, your storage assistant</a> <span>105</span></li><li><a href=\"/faq/settings/\">Settings &amp; keep-time</a> <span>88</span></li><li><a href=\"/faq/performance-battery/\">Performance &amp; battery</a> <span>62</span></li><li><a href=\"/faq/privacy-safety/\">Privacy &amp; safety</a> <span>85</span></li><li><a href=\"/faq/licensing-payments/\">Licensing &amp; payments</a> <span>131</span></li><li><a href=\"/faq/troubleshooting/\">Troubleshooting &amp; messages</a> <span>180</span></li><li><a href=\"/faq/comparisons/\">Comparisons &amp; alternatives</a> <span>75</span></li><li><a href=\"/faq/mac-storage-basics/\">Mac storage basics</a> <span>315</span></li></ul></details></aside><div class=\"fl-main\"><nav class=\"fl-crumbs\" aria-label=\"Breadcrumb\"><ol><li><a href=\"/\">Home</a></li><li><a href=\"/faq/\">FAQ</a></li><li><a href=\"/faq/backups/\">Backups &amp; restore points</a></li><li aria-current=\"page\">Why does the backup&#39;s time remaining keep changing?</li></ol></nav>\n<form class=\"fl-search\" action=\"/faq/search\" method=\"get\" role=\"search\" data-fl-search>\n<label class=\"fl-visually-hidden\" for=\"fl-q\">Search the FAQ</label>\n<input id=\"fl-q\" type=\"search\" name=\"q\" value=\"\" placeholder=\"Search 2,816 questions…\" autocomplete=\"off\" spellcheck=\"false\">\n<button type=\"submit\">Search</button>\n<div class=\"fl-suggest\" role=\"listbox\" hidden></div>\n</form>\n<article class=\"fl-entry\">\n<p class=\"eyebrow fl-eyebrow\"><a href=\"/faq/backups/\">Backups &amp; restore points</a> · <a href=\"/faq/backups/#speed-progress\">Speed, progress and the first backup</a></p>\n<h1>Why does the backup&#39;s time remaining keep changing?</h1>\n<p class=\"fl-short\"><strong>Short answer:</strong> The estimate follows the real transfer speed, which varies with file sizes, the cloud service and how busy your Mac is. Idle stalls are excluded, so it settles as the backup goes on.</p>\n<div class=\"fl-answer\"><p>Because it&#39;s worked out from the speed the backup is actually achieving, and that changes. Lots of small files move more slowly than a few big ones, cloud services vary through the day, and Storage Studio slows itself down when you&#39;re using the Mac heavily.</p>\n<p>Stalls don&#39;t distort it: time when nothing was moving is excluded from the estimate and shown separately as idle. Over a long backup the figure settles as it gets more to go on.</p></div>\n\n<p class=\"fl-meta\">Last reviewed <time datetime=\"2026-10-01\">October 1, 2026</time></p>\n\n<section class=\"fl-related\"><h2>Related questions</h2><ul><li><a href=\"/faq/backups/how-do-i-read-backup-progress\">How do I read the progress on a running backup?</a></li></ul></section>\n<p class=\"fl-formats\">Also available as <a href=\"/faq/backups/why-does-the-backup-time-left-keep-changing.md\">Markdown</a> and <a href=\"/faq/backups/why-does-the-backup-time-left-keep-changing.json\">JSON</a>.</p>\n</article></div></div></div>"}