Free SCORM validators and checkers compared: what each one checks

A SCORM package is a zip with a manifest (imsmanifest.xml, the file that tells the LMS what the course is and which page to open) and the course files. A validator catches the problems that make an LMS refuse the upload. Whether the course then completes, scores and resumes depends on what it says to the LMS while a learner clicks through, and only a tool that plays the course can see that. Below is what each free tool's own page says it does, as of October 2026, then where Alder differs.

Validators: check the zip without playing it

• Sodium Learn SCORM Validator: runs in your browser and says your package never leaves your device. It checks that the manifest exists and is valid XML and that the launch file is there, reports the SCORM version, and marks each check pass, warn or fail with an explanation. SCORM 1.2 and 2004; no account and no usage limits.
• Mindstamp SCORM Validator: runs in your browser with nothing uploaded, for zips up to 250 MB. It checks the manifest's place, form and declared version, that every file reference and the launch file resolve, that identifiers are unique, and that at least one SCO (a part of the course that reports to the LMS) exists. It reads SCORM 1.2 and 2004, and says it does not run the content. Its page also notes that an LMS may still reject a package that passes.
• Skillsail SCORM Validator: runs in your browser and never uploads the package. It checks the manifest's place and structure, the launch file and every referenced file, and letter-case mismatches that break on some servers. It recognizes SCORM 1.2, SCORM 2004, xAPI and cmi5 packages. Free, no sign-up.
• Teachfloor SCORM Validator: you upload the zip, and it checks it, the manifest against the SCORM 1.2 and 2004 specifications, file references, the launch file and the SCORM run-time API. It also reviews the course against WCAG accessibility guidelines (missing alt text, poor contrast, keyboard traps) and flags heavy files, common security issues and behaviour that can differ between browsers. Each check is marked passed or failed. Its “Validate your SCORM for free” button leads to a sign-up page.

Players and viewers: play the course and act as the LMS

• Skillsail SCORM Player: plays SCORM 1.2 and 2004 in your browser without uploading. It shows the completion and success status the course reports, the score, a live log of the API calls, and how much suspend data the course stores, flagging SCORM 1.2's 4,096-character limit. xAPI and cmi5 playback is “on the roadmap”.
• SCORM Lab: plays SCORM 1.2 and 2004 on your machine. It lists every call with its return code and shows the data model as a tree, compares snapshots between calls, lets you step back through an attempt, draws SCORM 2004 sequencing live, and has an authoring linter. Free; playing your own package needs a one-time email code.
• Nate Stoker's SCORM Viewer: drag in a zip to preview and test SCORM 1.2 and 2004 content, including Storyline and Rise. Its tabs show a console of API calls, the data model and the files, and an accessibility tab scans each slide against WCAG A, AA or AAA and exports the results.
• XtoSCORM SCORM Viewer: you upload a zip of up to 100 MB (the page says uploads are deleted after processing). It plays SCORM 1.2 and 2004, checks completion, score and that suspend data is saved and read back, and helps find missing files and broken links.
• EducateMe and SkillStudio offer free viewers, with no registration, for SCORM 1.2 and 2004 courses. EducateMe says its viewer shows the course as a learner would see it; SkillStudio says you can view, inspect and extract the files. Neither page describes tracking checks.

Where Alder is different

Alder runs the zip checks (where the manifest is, whether it is valid, missing files, letter case) and plays the course in your browser, without uploading it. Then:

• It predicts what the LMS will record: finished or not, passed or failed, the score, and what happens next time. We checked these predictions against SCORM Cloud in September 2026.
• It explains why, in your tool's own setting names. Alder recognizes Storyline 360, Rise 360 and Captivate and reads their tracking settings, so a problem comes with the setting to change, such as a quiz pass mark that differs from the manifest's mastery score.

• It watches saved progress. suspend_data is the text a course saves so learners can resume. A meter shows how much of SCORM 1.2's 4,096 characters the course uses, and a “Must fix” finding appears when it goes over. Skillsail's player flags the limit too.

• It tests resume. “Test as a returning learner” reopens the course with what it saved, to check it picks up where you left off.
• It plays xAPI and cmi5 too, with its own stand-in for the Learning Record Store (where those courses send their results), so there is nothing to set up.
• It knows seven LMSs. Alder says whether SAP SuccessFactors, Moodle, Workday Learning, Cornerstone, Canvas, Docebo and TalentLMS would record the same result. These notes come from vendor documentation and author reports: documented, not yet verified in each LMS.
• It fixes the zip. For Storyline and Rise, change settings such as the pass mark, and words and images, in the published zip and check it again. Every check and fix is free; downloading the edited zip is part of Pro ($19 a month or $149 a year).

Where other free tools do more

• Accessibility. Teachfloor's validator and Nate Stoker's viewer offer WCAG checks. Alder has no accessibility checks today; use one of them, or your authoring tool's own checker.
• Performance and browsers. Teachfloor's page says it flags heavy files and behaviour that can break in some browsers. Alder runs the course in your one browser, so it can't show Safari or iPad problems.
• Developer depth. SCORM Lab's data-model tree, snapshot comparison and step-back suit developers who want to see every value change. Its sequencing view shows SCORM 2004 sequencing running; Alder plays one SCO at a time and explains sequencing in words without running it.

Which to use

• The LMS rejects the upload: any validator above, or Alder, will find it. See “imsmanifest.xml not found”.
• It uploads but won't complete, score or resume: you need a tool that plays it. A player with a call log shows what happened; Alder also says why and what to change.
• You need the reference record for an LMS vendor or a client: SCORM Cloud. See Alder vs SCORM Cloud.

Try it

Drop your published zip into Alder, or click “Try a sample course” under the drop zone to see the checks, the player and the prediction on a course we made. It is free, with no account, and your course never leaves your browser.