Tools
Nine everyday developer tools, bundled into one local app. Press ⌘K from anywhere in Umbra to jump straight to any of them.
JSON
Format, validate, explore, diff, and repair JSON.
Base64
Encode and decode text or files, including drag-and-drop.
UUID
Generate v4 or v7 identifiers, one at a time or in bulk.
Hash
Compute SHA-2, SHA-3, MD5, and SHA-1 digests of text or a file.
JWT
Decode a token's header and payload — reads, doesn't verify.
Cron
Build a 5-field cron expression with a guided grid.
Image to Text
Pull text out of a screenshot or scan with a bundled AI model.
PDF
Merge, reorder, rotate, delete, and read text from PDF pages.
Images
Convert, resize, and compress PNG, JPEG, WebP, and AVIF.
A wider comparison
Not just the three named desktop competitors, but the two other categories the same decision usually comes down to. See the individual write-ups: DevToys, DevUtils, DevTools-X, CyberChef.
| Umbra | Web-based tools | Other desktop toolboxes | |
|---|---|---|---|
| Where your data goes | Stays on your machine. One disclosed exception: an automatic check for app updates, at launch. | Sent to a server you don't control, even if only for a second. | Local, for the tools that are — check each one; "desktop" doesn't guarantee offline-only. |
| How you can verify that | A documented, repeatable network-monitor check you run yourself. | No way to verify — you're trusting the server operator. | States the claim in a sentence; no published verification mechanism found for DevToys, DevUtils, or DevTools-X as of 2026-09-19. |
| Works without an internet connection | Yes — a native app, no server dependency. | No — needs a live connection to the tool's own server. | Yes, once installed. |
| Cost | Free, no account. | Usually free, often ad-supported. | Free (DevToys, DevTools-X) or paid (DevUtils). |
| Local AI feature | Yes — offline OCR (Image to Text), a bundled model, nothing uploaded. | N/A. | None found, across DevToys, DevUtils, or DevTools-X, as of 2026-09-19. |