Why do thermal receipts fade so quickly?+
Thermal paper is coated with a heat-reactive dye (usually a leuco dye + developer like BPA/BPS). Heat, sunlight, oils, plasticisers in plastic wallets, and even time itself trigger the same chemical reaction that printed the receipt — except evenly across the page, so contrast disappears. Most thermal receipts become hard to read within 6–24 months under normal conditions.
Can ThermalScan actually recover faded text, or just darken the whole image?+
Both, and in that order. The Adaptive Threshold pass analyses each small neighbourhood of the image independently, so faint regions get aggressive contrast while clean regions are left alone. Gamma correction recovers mid-tones from chemically-degraded ink, and the sharpness pass re-defines character edges. The result is closer to "reveal" than "darken" — though if a receipt is completely blank, no software (this or any other) can recover what is no longer there.
Does my receipt leave my computer?+
No. Every operation — file read, image processing, contrast adjustments, download — runs in your browser using Canvas APIs. The Inventera server never receives the image. You can verify this in your browser DevTools: load the tool, upload a receipt, and confirm zero network requests carry the file payload.
Is this acceptable for an IRS or HMRC tax audit?+
A restored thermal receipt is generally accepted by tax authorities as long as the original information (date, vendor, amount, line items) is legibly visible after restoration and the restoration is non-destructive (no information added). Best practice: keep the original alongside the restored copy, label both with the restoration date, and store as PDF. Inventera does not provide legal advice — check with your accountant for jurisdiction-specific rules.
What image formats does it accept?+
PNG, JPG/JPEG, WebP, and HEIC where browser support exists. For best results, photograph the receipt under flat lighting at 300+ DPI equivalent (most modern phone cameras exceed this). Avoid flash — it creates highlights that confuse the adaptive threshold pass.
How is this different from Adobe Scan or Receipt Bank?+
Adobe Scan and Receipt Bank are cloud OCR services — they upload your receipt to extract text and integrate with accounting software. ThermalScan is the opposite: it does image restoration only, locally, with no cloud. Use ThermalScan when the receipt is too faded for OCR to even attempt, then feed the restored image into whatever OCR pipeline you prefer.
Is there a usage limit or signup?+
No limit, no signup, no email required. All processing power is your own browser. Use it on as many receipts as your CPU can keep up with.
Can I use the tool offline?+
Once the page has loaded in your browser, the actual image processing works without an internet connection. A standalone PWA build is on the roadmap for fully air-gapped use.