{"id":"data-transfers.what-is-bidirectional-sync","url":"/faq/data-transfers/what-is-bidirectional-sync","category":{"id":"data-transfers","title":"Data Transfers"},"subcategory":{"id":"operations","title":"Copy, Move and Sync"},"question":"What is Bidirectional sync and when should I use it?","alt_questions":["two-way sync storage studio","keep two folders in sync both ways","How does two way sync work?","bisync mac app","sync changes in both directions","What does Bidirectional sync do?","two way sync between Mac and cloud"],"short_answer":"Bidirectional sync carries changes, including deletions, in both directions between two places, recording conflicts in the log. Tick “First run for this pair” on the very first run, then never again.","answer_markdown":"**Bidirectional sync** keeps two places matched in both directions: a change made on either side — a new file, an edit, a deletion — is carried across to the other the next time it runs. If the same file was changed on both sides, that conflict is recorded in the transfer's log.\n\nUse it when you genuinely work in both places, for example a project folder on your Mac and the same folder in a cloud account you also edit from another computer. If changes only ever flow one way, **Sync (one-way)** is simpler and safer.\n\nTwo things to know:\n\n- The very first run for a pair of folders needs the **First run for this pair** option ticked.\n- Pair it with a schedule so it keeps running without you.\n\nRelated: [The First run for this pair option](/faq/data-transfers/first-run-for-this-pair-option) · [Schedule a transfer](/faq/data-transfers/schedule-a-recurring-transfer)","answer_html":"<p><strong>Bidirectional sync</strong> keeps two places matched in both directions: a change made on either side — a new file, an edit, a deletion — is carried across to the other the next time it runs. If the same file was changed on both sides, that conflict is recorded in the transfer&#39;s log.</p>\n<p>Use it when you genuinely work in both places, for example a project folder on your Mac and the same folder in a cloud account you also edit from another computer. If changes only ever flow one way, <strong>Sync (one-way)</strong> is simpler and safer.</p>\n<p>Two things to know:</p>\n<ul><li>The very first run for a pair of folders needs the <strong>First run for this pair</strong> option ticked.</li><li>Pair it with a schedule so it keeps running without you.</li></ul>\n<p>Related: <a href=\"/faq/data-transfers/first-run-for-this-pair-option\">The First run for this pair option</a> · <a href=\"/faq/data-transfers/schedule-a-recurring-transfer\">Schedule a transfer</a></p>","answer_text":"Bidirectional sync keeps two places matched in both directions: a change made on either side — a new file, an edit, a deletion — is carried across to the other the next time it runs. If the same file was changed on both sides, that conflict is recorded in the transfer's log.\n\nUse it when you genuinely work in both places, for example a project folder on your Mac and the same folder in a cloud account you also edit from another computer. If changes only ever flow one way, Sync (one-way) is simpler and safer.\n\nTwo things to know:\n\n- The very first run for a pair of folders needs the First run for this pair option ticked.\n- Pair it with a schedule so it keeps running without you.\n\nRelated: The First run for this pair option · Schedule a transfer","tags":["two-way sync","bidirectional","sync","conflicts"],"related":[{"id":"data-transfers.first-run-for-this-pair-option","question":"What does the “First run for this pair” option do in a two-way sync?","url":"/faq/data-transfers/first-run-for-this-pair-option"},{"id":"data-transfers.bidirectional-sync-conflicts","question":"What happens if the same file changes on both sides of a two-way sync?","url":"/faq/data-transfers/bidirectional-sync-conflicts"},{"id":"data-transfers.schedule-a-recurring-transfer","question":"How do I schedule a transfer to run automatically?","url":"/faq/data-transfers/schedule-a-recurring-transfer"}],"applies_to":"all","last_reviewed":"2026-10-01","title":"What is Bidirectional sync and when should I use it? — Storage Studio FAQ","description":"Bidirectional sync carries changes, including deletions, in both directions between two places, recording conflicts in the log. Tick “First run for this pair” on the very first run, then never again.","crumbs":[{"name":"Home","path":"/"},{"name":"FAQ","path":"/faq/"},{"name":"Data Transfers","path":"/faq/data-transfers/"},{"name":"What is Bidirectional sync and when should I use it?","path":"/faq/data-transfers/what-is-bidirectional-sync"}],"jsonld":{"@context":"https://schema.org","@type":"FAQPage","url":"https://storagestudio.us/faq/data-transfers/what-is-bidirectional-sync","inLanguage":"en","dateModified":"2026-10-01","mainEntity":[{"@type":"Question","name":"What is Bidirectional sync and when should I use it?","alternateName":["two-way sync storage studio","keep two folders in sync both ways","How does two way sync work?","bisync mac app","sync changes in both directions","What does Bidirectional sync do?","two way sync between Mac and cloud"],"acceptedAnswer":{"@type":"Answer","text":"Bidirectional sync keeps two places matched in both directions: a change made on either side — a new file, an edit, a deletion — is carried across to the other the next time it runs. If the same file was changed on both sides, that conflict is recorded in the transfer's log.\n\nUse it when you genuinely work in both places, for example a project folder on your Mac and the same folder in a cloud account you also edit from another computer. If changes only ever flow one way, Sync (one-way) is simpler and safer.\n\nTwo things to know:\n\n- The very first run for a pair of folders needs the First run for this pair option ticked.\n- Pair it with a schedule so it keeps running without you.\n\nRelated: The First run for this pair option · Schedule a transfer","url":"https://storagestudio.us/faq/data-transfers/what-is-bidirectional-sync"}}]},"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 class=\"fl-open\"><a href=\"/faq/data-transfers/\" aria-current=\"true\">Data Transfers</a> <span>119</span><ul><li><a href=\"/faq/data-transfers/#basics\">Data Transfers basics</a> <span>12</span></li><li class=\"fl-on\"><a href=\"/faq/data-transfers/#operations\">Copy, Move and Sync</a> <span>10</span></li><li><a href=\"/faq/data-transfers/#downloads\">Downloads and large files</a> <span>13</span></li><li><a href=\"/faq/data-transfers/#setting-up\">Setting up a transfer</a> <span>13</span></li><li><a href=\"/faq/data-transfers/#scheduling\">Scheduling transfers</a> <span>13</span></li><li><a href=\"/faq/data-transfers/#progress-and-control\">Progress, pausing and history</a> <span>12</span></li><li><a href=\"/faq/data-transfers/#drive-and-space\">External drive and disk space</a> <span>9</span></li><li><a href=\"/faq/data-transfers/#speed-and-advanced\">Speed and advanced options</a> <span>9</span></li><li><a href=\"/faq/data-transfers/#devices-and-plan-storage\">Paired devices and plan storage</a> <span>9</span></li><li><a href=\"/faq/data-transfers/#problems\">Problems and messages</a> <span>12</span></li><li><a href=\"/faq/data-transfers/#privacy-and-reporting\">Privacy, safety and reporting</a> <span>7</span></li></ul></li><li><a href=\"/faq/backups/\">Backups &amp; restore points</a> <span>126</span></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/data-transfers/\">Data Transfers</a></li><li aria-current=\"page\">What is Bidirectional sync and when should I use it?</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/data-transfers/\">Data Transfers</a> · <a href=\"/faq/data-transfers/#operations\">Copy, Move and Sync</a></p>\n<h1>What is Bidirectional sync and when should I use it?</h1>\n<p class=\"fl-short\"><strong>Short answer:</strong> Bidirectional sync carries changes, including deletions, in both directions between two places, recording conflicts in the log. Tick “First run for this pair” on the very first run, then never again.</p>\n<div class=\"fl-answer\"><p><strong>Bidirectional sync</strong> keeps two places matched in both directions: a change made on either side — a new file, an edit, a deletion — is carried across to the other the next time it runs. If the same file was changed on both sides, that conflict is recorded in the transfer&#39;s log.</p>\n<p>Use it when you genuinely work in both places, for example a project folder on your Mac and the same folder in a cloud account you also edit from another computer. If changes only ever flow one way, <strong>Sync (one-way)</strong> is simpler and safer.</p>\n<p>Two things to know:</p>\n<ul><li>The very first run for a pair of folders needs the <strong>First run for this pair</strong> option ticked.</li><li>Pair it with a schedule so it keeps running without you.</li></ul>\n<p>Related: <a href=\"/faq/data-transfers/first-run-for-this-pair-option\">The First run for this pair option</a> · <a href=\"/faq/data-transfers/schedule-a-recurring-transfer\">Schedule a transfer</a></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/data-transfers/first-run-for-this-pair-option\">What does the “First run for this pair” option do in a two-way sync?</a></li><li><a href=\"/faq/data-transfers/bidirectional-sync-conflicts\">What happens if the same file changes on both sides of a two-way sync?</a></li><li><a href=\"/faq/data-transfers/schedule-a-recurring-transfer\">How do I schedule a transfer to run automatically?</a></li></ul></section>\n<p class=\"fl-formats\">Also available as <a href=\"/faq/data-transfers/what-is-bidirectional-sync.md\">Markdown</a> and <a href=\"/faq/data-transfers/what-is-bidirectional-sync.json\">JSON</a>.</p>\n</article></div></div></div>"}