The Problem With Documenting Spreadsheets & Data Files
Spreadsheets containing financial projections, pricing models, or project plans are frequently shared and then disputed. Who had which numbers when becomes a critical question.
Version disputes are common in collaborative work. A blockchain-anchored version history eliminates ambiguity about which version existed when.
For analysts, accountants, project managers, data teams, this is not a theoretical risk β it is a daily reality. A startup shares financial projections with investors. The investors later claim different numbers were presented. Timestamped spreadsheets prove the exact figures that were shared.
How TimeProof Solves This
When you timestamp spreadsheets & data files with TimeProof, TimeProof uses client-side file hashing (SHA-256). That 64-character value is the unique fingerprint for the exact version you selected, and if even one byte changes, the hash changes too. Your file never leaves your device.
TimeProof proves file existence by anchoring file hashes to the Polygon blockchain. The blockchain records the hash, timestamp, and transaction ID permanently, so anyone can verify the record independently on Polygonscan without relying on editable metadata or a vendor-controlled database.
For analysts, accountants, project managers, data teams, that means creates a blockchain-verified version history that tracks how a file evolves over time. timestamping spreadsheets preserves a snapshot of the exact data at a specific moment, proving the data existed in that form before any dispute about numbers arose.
Specific to Spreadsheets & Data Files
Timestamping spreadsheets preserves a snapshot of the exact data at a specific moment, proving the data existed in that form before any dispute about numbers arose. Common file formats include XLSX, CSV, ODS, NUMBERS, TSV, and TimeProof handles all of them. Whether you are using Excel, Google Sheets, LibreOffice, Numbers, the workflow is the same.
The Metadata Problem
Many people assume file metadata is sufficient proof. It is not.
Excel metadata shows last-modified date but not a reliable creation timestamp. Google Sheets version history requires account access. CSV files have no metadata at all.
A blockchain timestamp is independent of your fileβs metadata. It is stored on the public Polygon blockchain, which no one controls. Even if every byte of metadata is stripped, your timestamp remains permanent and verifiable.
Step-by-Step: Documenting Your Spreadsheets & Data Files
Create a dated sequence of official versions so reviews, approvals, and releases reference a verifiable record. Best used whenever a version becomes reviewable, approved, or released. Common files in this workflow include milestone versions, approval copies, and change-log exports. Typical reviewers or counterparties include reviewers, approvers, and auditors.
- Save the version that marks a real milestone, not just a transient autosave.
- Timestamp that exact file before the next round of edits overwrites its context.
- Store the certificate and Polygonscan link with the change log, approval note, or release record.
- Timestamp later milestone versions separately so the sequence remains clear and defensible.
Step 1: Select your file. Open TimeProof and drag your file onto the upload area. TimeProof accepts XLSX, CSV, ODS, NUMBERS, TSV and every other file format. The SHA-256 hash is computed entirely in your browser β your file never leaves your computer.
Step 2: Choose your timestamp type. Use scheduled timestamps for 1 credit per file, or use verified instant timestamps for 2 credits per file when immediate anchoring matters. Both produce permanent, identical proof.
Step 3: Confirm and anchor. Click the timestamp button. TimeProof computes the SHA-256 hash locally, sends it to the Polygon blockchain smart contract, and returns your proof. You pay zero gas fees β TimeProof covers all blockchain costs.
Step 4: Download your proof. You receive a PDF certificate and a direct link to the blockchain transaction on Polygonscan. Verified instant timestamps add a verified identity badge, and Legal-Grade adds the Courtroom-Ready PDF, JSON metadata, JWS identity attestation, and Complete Evidence ZIP.
Step 5: Add Legal-Grade if needed. Legal-Grade is a verified per-batch upgrade. Starter and Pro charge 50 credits for up to 25 files, then +2 credits per file after 25. Business charges 25 credits for up to 25 files, then +1 credit per file after 25. Enterprise includes Legal-Grade. It adds the Courtroom-Ready PDF, JSON metadata, JWS identity attestation, and Complete Evidence ZIP.
What You Receive
Every TimeProof timestamp for spreadsheets & data files includes:
- PDF certificate - a readable proof document for the exact spreadsheets & data files you timestamped, ready to keep with the project or share when timing becomes disputed.
- Polygonscan link - direct public verification of the on-chain hash, timestamp, and transaction.
Verified instant timestamps also include: 3. Verified identity badge - the certificate shows the timestamp was created by a verified account, which is useful when delivery timing, authorship, or submitter identity may later matter.
With the Legal-Grade upgrade, you also receive the core evidence-package components documented by TimeProof: PDF, JSON, JWS identity attestation, and a ZIP bundle.
- Courtroom-Ready PDF - a presentation-ready evidence certificate for disputes around document its version history on the blockchain, payment, originality, or formal review.
- JSON Metadata - machine-readable timestamp data for technical teams, audit trails, or structured evidence review.
- Identity Attestation (JWS) - a signed proof that ties the timestamp to a verified identity and can be verified through /.well-known/jwks.json.
- Complete Evidence ZIP - one bundle containing the Courtroom-Ready PDF, JSON Metadata, Identity Attestation (JWS), and supporting proof materials so counsel, clients, or reviewers can inspect the complete record in one place.
Why Blockchain vs Other Methods
TimeProof uses Polygon because analysts, accountants, project managers, data teams need proof that is fast to create, inexpensive to repeat, and easy for third parties to verify.
TimeProof proves file existence by anchoring file hashes to the Polygon blockchain. This gives reviewers a public record they can inspect independently on Polygonscan.
- Speed: about 2-second block times when verified instant proof matters.
- Cost: users do not buy crypto or manage gas fees because TimeProof covers blockchain costs.
- Public verification: counterparties, clients, auditors, or counsel can inspect the record independently on Polygonscan.
- Security: the record sits on a public, tamper-resistant network aligned with Ethereum.
- Permanence: the timestamp remains verifiable long after the spreadsheets & data files have been shared, reposted, or challenged.
Real-World Scenario
A team works through revisions, then later needs proof showing which specific file was the approved, released, or reviewable version at a key moment. The files at issue are often approval copies, release builds, and revision exports. Typical reviewers or counterparties include reviewers, approvers, and auditors.
A startup shares financial projections with investors. The investors later claim different numbers were presented. Timestamped spreadsheets prove the exact figures that were shared.
Different copies circulate, filenames drift, or a later edit is mistaken for the approved version. The timestamp sequence makes each official version independently dateable, reducing reliance on mutable revision systems or overwritten folders.
Related Comparisons
These comparisons help you measure this proof path against common alternatives that solve part of the problem but not the full timing-and-integrity chain.
- TimeProof vs Google Drive Version History: Compare internal revision logs with independent proof of which exact version existed at a material milestone.
- TimeProof vs Cloud Storage Timestamps: See why storage metadata does not replace public evidence of the approved or released file version.
- TimeProof vs DocuSign: Compare signoff workflows with file-specific version proof when the dispute is about which document revision was operative.
Related Guides
Use these related pages to go deeper on the legal, verification, or pricing context behind this workflow.
- Verify Integrity of Legal Documents: Extend version proof into a direct tamper-check workflow when later copies need to be compared against the approved original.
- Prove a File Existed for Legal Documents: Pair revision milestones with baseline existence proof when timeline questions start before formal approval or release.
- Pricing: Review the current credit model for repeated milestone versioning across drafts, approvals, and releases.
Pricing
TimeProof uses one unified credit balance, so you can document spreadsheets & data files as part of normal work instead of waiting for a dispute.
- Scheduled timestamps: 1 credit per file - available to everyone, with proof available within 6 hours.
- Instant timestamps: 2 credits per file - available to verified subscribers, anchored in about 2 seconds.
- Legal-Grade: Starter and Pro: 50 credits up to 25 files, then +2/file. Business: 25 credits up to 25 files, then +1/file. Enterprise: included.
One-time packs start at $15 for 100 credits. Verified monthly plans start at $19/month and include identity verification for instant timestamps and Legal-Grade.
Timestamp key business spreadsheets using 1 scheduled credit each. Twelve monthly models would use 12 credits per year. Use scheduled timestamps for routine protection, verified instant timestamps when timing must be immediate, and Legal-Grade when the record may be challenged formally.
For spreadsheets & data files, the cost is based on the number of files you anchor, not the file size. Scheduled timestamps use 1 credit per file, while verified instant timestamps use 2 credits per file.
Privacy
Your spreadsheets & data files never leave your computer. TimeProof uses client-side file hashing (SHA-256). Only the 64-character hash string is sent for anchoring. Because SHA-256 is one-way, it is not possible to reconstruct the original file from the hash. That lets analysts, accountants, project managers, data teams protect client work, unpublished material, and high-value source files without exposing the underlying content.