Compare two PowerPoint decks — slide by slide, in your browser
To compare two PowerPoint decks, drop both .pptx files into Diffesq: it pairs slides across the two versions and shows which slides were added, removed, moved, or edited — with word-level text changes and a visual preview of each slide — without uploading either deck. Slides are matched by content, so inserting one slide never cascades false changes onto the rest of the deck.
Because everything runs locally in your browser, it suits decks you can't send to a third-party service: board and pitch decks, client presentations, anything confidential.
How it works
- Open the Diffesq workbench and drop a .pptx deck on each side.
- Diffesq parses both decks on your device and pairs slides by content.
- Review each slide pair's status — unchanged, modified, added, removed, or moved — with word-level text highlights, or switch to the visual preview to catch purely visual edits. An ordered change panel lists every change and jumps both sides to the affected slide.
- Export a change report with before/after images of the changed slides (Pro) — generated locally, never server-side.
What the comparison covers
- Slide pairing with a per-pair status; a relocated slide is reported as moved, never as an unrelated delete and insert.
- Word-level text comparison across placeholders, text boxes, shapes, grouped shapes, and SmartArt. Charts are compared by their text and data — titles, axis and series labels, category names, and data values — not treated as opaque images, so a changed number is caught even when the chart looks the same.
- Speaker notes and tables are compared; images are compared by identity.
- A faithful visual preview renders both slides — theme colors, fonts, positioned shapes, and images — so visual-only edits show up even when no text changed; it degrades to a clearly-labeled schematic preview when faithful rendering isn't possible.
- Missing fonts: Diffesq asks before fetching any font from the network, and renders with a close substitute if you decline. Nothing about your deck is ever uploaded.
Free vs Pro
Structured-file comparisons run in full on your device on the free tier, with about a third of the results shown as a preview; Pro unlocks the complete results and clean, unwatermarked exports (HTML, Markdown, JSON, PDF).
See Pricing for plans — $6/month, $48/year, or $119 once.
Privacy
Every comparison runs locally in your browser. Your files are never uploaded — there is no server that receives them, and the page keeps working with Wi-Fi turned off. Details in the Privacy Policy.
Frequently asked questions
Does it rebuild or redline the .pptx?
No — Diffesq produces a change report plus before/after images of the changed slides. It compares and reports; it doesn't edit, merge, or reconstruct the deck.
Does it compare charts?
Yes — charts are compared by their titles, axis and series labels, category names, and data values, so a changed value is caught even when the chart looks identical.
Does it work offline?
Yes — once the page has loaded, parsing, comparing, and rendering all happen on your device. Turn off Wi-Fi and it still works.
Do I need an account?
No. Comparisons run without any signup. Pro features unlock with a license key — still no account or login.