# Balena Etcher - Image Integrity **URL:** \ **Category:** balenaEtcher\ **Created:** [August 30, 2024, 5:50pm UTC](https://forums.balena.io/t/balena-etcher-image-integrity/371262 "2024-08-30T17:50:10Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![jeremisu](https://avatars.discourse-cdn.com/v4/letter/j/74df32/32.png) [@jeremisu](https://forums.balena.io/u/jeremisu)\ **Post date:** [August 30, 2024, 5:50pm UTC](https://forums.balena.io/t/balena-etcher-image-integrity/371262/1 "2024-08-30T17:50:10Z")
Hi, I’m using Balena Etcher to write .iso to a bootable USB. It’s been working without any issues but I see when the flash after flashing is completed on the UI, Etcher shows a progress bar for validation. I am curious what the process of image validation is. How does Etcher check that the image was copied over successfully? ---
**Author:** ![joshbwlng](https://sea2.discourse-cdn.com/balena/user_avatar/forums.balena.io/joshbwlng/32/10307_2.png) [@joshbwlng](https://forums.balena.io/u/joshbwlng)\ **Post date:** [September 6, 2024, 6:44am UTC](https://forums.balena.io/t/balena-etcher-image-integrity/371262/2 "2024-09-06T06:44:02Z")
Hi, balenaEtcher validates using the expected checksum. As balenaEtcher is open source you can check our GitHub repositories and see exactly how the validation logic works for yourself if you’d like. Perhaps you’ll find these links useful: - [etcher/lib/util/child-writer.ts at master · balena-io/etcher · GitHub](https://github.com/balena-io/etcher/blob/master/lib/util/child-writer.ts#L149) - [etcher-sdk/lib/multi-write.ts at master · balena-io-modules/etcher-sdk · GitHub](https://github.com/balena-io-modules/etcher-sdk/blob/master/lib/multi-write.ts#L109) ---
**Author:** ![jeremisu](https://avatars.discourse-cdn.com/v4/letter/j/74df32/32.png) [@jeremisu](https://forums.balena.io/u/jeremisu)\ **Post date:** [September 6, 2024, 2:39pm UTC](https://forums.balena.io/t/balena-etcher-image-integrity/371262/3 "2024-09-06T14:39:26Z")
Thank you this is perfect!