Check file names and build size-limited ZIP downloads

1At a glance

• You chooseA product folder, a few files, or a ZIP you already made.
• DraupnirFlow checksFile names Windows refuses, Mac and Windows system files, case clashes, long paths and old ZIP problems — and fixes the names it can.
• You getOne or more complete ZIP files that each fit your limit, plus a text or JSON report of every change.

The built-in Etsy digital listing preset follows Etsy’s published limits: at most 5 files of 20 MB each, and upload file names of at most 70 letters, digits, periods, underscores or hyphens. DraupnirFlow treats 20 MB as 20,000,000 bytes, the stricter reading. For other shops, enter your own limits.

Tested: desktop Google Chrome 152 on Linux. Not tested: Windows, macOS, phones and other browsers, and real uploads to Etsy.

2Install and open

1. Extract the whole download. Unzip DraupnirFlow-1.0.1.zip into a folder you keep, for example Documents/DraupnirFlow. Do not open files from inside the ZIP.
2. Keep the folders together. DraupnirFlow.html loads its code from the app folder next to it. Moving the HTML file on its own stops the buttons from working.
3. Open DraupnirFlow.html in Google Chrome — drag it onto a Chrome window, or right-click it and choose Open with → Google Chrome. No installation, account or internet connection is needed.

3Make your first ZIP with the included example

You will create Cozy-Planner-Bundle.zip from the fictional practice folder that comes with DraupnirFlow. It takes six steps.

1. Choose the practice folder. Click Choose product folder… and select examples/Cozy Planner Bundle. If Chrome asks whether to “upload” the files, it is asking to let this local page read them; nothing is sent anywhere.
2. Leave the settings as they are. Shop limits stays on Etsy digital listing. After you choose the folder, the settings fold into one line — “Cozy Planner Bundle” · Etsy digital listing: up to 5 ZIP files of 20.00 MB · unzip guide added — and the page moves to the review. Click Change to open them again.
3. Read the review. The amber banner says what happens next.

   Ready to build 1 ZIP file — check 4 warnings first. 12 of 15 files included · 3 left out · 4 fixed automatically · 1.79 MB in 1 of at most 5 ZIP files. The ZIP plan shows Cozy-Planner-Bundle.zip with 13 files at 8.9% of the limit.

   The four warnings are deliberate in this practice folder: an empty file, a ZIP inside the folder and two non-English file names. With your own product, decide about each warning before you build.
4. Build. Click Build ZIP files.
5. Save the ZIP and the report. Click Download next to Cozy-Planner-Bundle.zip, then Download report (.txt). Chrome saves both in its usual download folder.

   The row turns green and says Download started. The ZIP is 1,788,188 bytes and holds 13 files.

6. Open the saved ZIP. Extract it: you get the 12 product files and How to open these files.txt. That completes the practice run. For your own product, choose its folder and review the findings again.

The complete worked example

All 15 files in examples/Cozy Planner Bundle and what DraupnirFlow does with each one:

Output: Cozy-Planner-Bundle.zip — 12 product files plus How to open these files.txt, 1,788,188 bytes, 8.9% of the 20,000,000-byte limit. The name follows Etsy’s file-name rule, so “Cozy Planner Bundle” becomes Cozy-Planner-Bundle.zip.

4Read the review

• The banner is green when the ZIP files are ready, amber when there are warnings to check and red when something blocks the build. Below the title it counts the files found, included and left out, the automatic fixes, and the total size.
• ZIP plan lists each ZIP that will be built, its exact size and how full it is. The names you see here are exactly the names you will download.
• Findings explain every problem. Blocking stops the build, Warning is for you to judge, Fixed was handled automatically. The filter buttons show one group at a time.
• Renamed files (fold-out under the findings) puts each original name next to its new name in the ZIP.

5Large products and Etsy’s 5 × 20 MB limit

When a product is bigger than one ZIP may be, DraupnirFlow spreads it over several complete ZIP files. Each part opens on its own — there are no .z01 split volumes — and every file is compressed before planning, so the exact size of each ZIP is known in advance and none exceeds the limit. Top-level folders stay together when they fit. With the Etsy preset the parts are named Product-Name-Part-1-of-3.zip and so on; the stem is shortened when needed so the longest name stays within 70 characters.

The pictures in this section use a larger synthetic practice folder, “Spring Printables Shop Bundle” (44 files, 45.21 MB), made with examples/make_examples.py --messy DIR --big --benign. Your own numbers will differ.

On Etsy, upload each ZIP as a separate digital file in your listing.

6Downloads and the report

Download report (.txt) and (.json) save a record of the settings, every finding, every rename and each ZIP’s size and SHA-256 checksum. Use the JSON file if you want to process the record with another tool. The start of the report for the practice folder:

DraupnirFlow 1.0.1 report — 2026-10-01T08:19:23.581Z
Source: Folder "Cozy Planner Bundle"
Product: Cozy Planner Bundle
Limits: 5 ZIP file(s), 20.00 MB (20000000 bytes) each
Files: 15 found, 12 included, 3 left out
Findings: 0 blocking, 4 fixed automatically, 4 warnings

ZIP files
---------
* Cozy-Planner-Bundle.zip — 1788188 bytes, 13 files, SHA-256 c80d4c565b02c8a414e633c8996c4cbfe07419d6e5200f9611600cda3adeb012

Your date and checksum will differ: the unzip guide inside each ZIP carries the time you built it.

Reports list your file names. If the names contain client or personal information, review a report before you share it.

7When building is blocked

While any finding is Blocking, the banner is red and Build ZIP files stays disabled. Each case below gives the cause, what to do, and how you know it worked.

• Too many ZIP files — the product needs more ZIP files than your limit allows. Remove or shrink files, or split the product into separate listings. Do not raise the Etsy numbers to get around it: Etsy’s own limit still applies.
• File too large for one ZIP — one file is bigger than the limit even after compression. Export a smaller version, or deliver that file another way.
• Damaged entry, Password-protected entry or Unsupported compression in an existing ZIP — rebuild from your original files instead.

After you change files on disk, choose the folder again so DraupnirFlow reads the new versions. It worked when the banner turns amber or green and the Build button is enabled.

8Check and repair a ZIP you already made

1. Click Check an existing ZIP… and pick the ZIP. To follow along, pick examples/old-shop-download.zip.
2. Read the findings. Names stored without UTF-8 flag means some unzip tools may show garbled names such as Résumé instead of Résumé.
3. Click Build ZIP files to make a clean copy: names are fixed and stored with the UTF-8 flag, and system files are left out. Your original ZIP is not changed.

Names that still look wrong

Old ZIPs without the UTF-8 flag do not say which character set they use. DraupnirFlow reads such a name as UTF-8 when the bytes are valid UTF-8. Otherwise it guesses the old DOS character set (code page 437) and shows a Warning, because the guess can be wrong. If names look garbled, choose another Name encoding for old ZIPs without the UTF-8 flag — it appears in step 1 when you check a ZIP — for example Shift_JIS for ZIPs made on Japanese Windows. DraupnirFlow then reads the ZIP again.

Entries that are never repacked

Entries with absolute paths or .. (they could write outside the buyer’s folder) and Unix symbolic links are left out with a warning. Password-protected, damaged and unsupported entries block the build. Either way they count as left out, and the banner says how many entries from the original ZIP cannot be repacked — the new ZIP never looks complete when it is not.

9Exact limits and supported formats

10Settings

Settings sit in step 2. After you choose files they fold into a one-line summary; click Change to open them. The review updates as you edit. While DraupnirFlow reads files or builds ZIP files, the settings are locked, so the plan, the downloads and the report always describe the same ZIP files.

11Findings reference

12Troubleshooting

The buttons do nothing.

Extract the whole DraupnirFlow-1.0.1.zip again and open DraupnirFlow.html from the extracted folder, with the app folder next to it. Then the start page shows Choose what buyers will download and the buttons open a file chooser.

Build ZIP files is disabled.

Click the Blocking filter, fix the cause it names (section 7), then choose the folder again. The button is enabled once the banner is no longer red.

Download all saved only one file.

Chrome may block several downloads from one page. Allow them when Chrome asks, or click each Download button. A row says Download started after you click it; Chrome’s download list shows which files actually arrived.

Names from an old ZIP look garbled.

Choose another Name encoding for old ZIPs in step 1 (section 8). The findings update with the new reading.

Will my ZIP open on every device, and will Etsy accept it?

DraupnirFlow follows Microsoft’s file-naming rules, the ZIP specification and Etsy’s published limits, and its output was verified with independent ZIP readers on Linux. It was not tested on Windows, macOS, iPhone or Android unzip apps, and nothing was uploaded to Etsy. Open your files once yourself before publishing.

Can I use it for Gumroad, Payhip or my own website?

Yes — choose Custom limits and enter that shop’s limits. DraupnirFlow knows only Etsy’s published limits.

Asking for help

Say which version you use (DraupnirFlow 1.0.1), your operating system and browser, the step number, the exact message, and whether the practice folder works. Do not send private customer files, passwords, order or recovery codes; a small fictional example is enough.

13Privacy, uninstall and limitations

Privacy

• Everything happens in your browser tab. The page makes no network requests (its security policy blocks them), has no accounts or analytics, and stores nothing. Closing or reloading the tab discards everything.
• Hidden files (names starting with “.”) are left out unless you include them.
• Downloads are saved by your browser in its usual download folder.

Uninstall

Delete the DraupnirFlow folder. It stores nothing elsewhere; the ZIP files and reports you saved stay where your browser put them.

Limitations

• Tested in desktop Google Chrome 152 on Linux only. Windows, macOS, phones, Edge, Firefox and Safari have not been tested. The page fits narrow windows, but processing on phones was not tested.
• No upload to Etsy or any shop, no shop connection, and no guarantee that a marketplace accepts a file or that every unzip app opens it.
• File contents (PDF pages, images, licences, personal data) are not inspected, and archives inside your product are not opened.
• The path-length warning is an estimate based on the buyer folder you set; actual limits depend on Windows settings.
• A guessed encoding for an old ZIP can be wrong; check names flagged as warnings.