IAB · TCF v2
TCF Consent String Decoder
Online TCF v2 decoder: paste one consent string for a detailed breakdown (purposes, vendors, CMP, dates) — or switch to bulk analysis to audit an entire CMP export, 100% in your browser. Vendor names are not yet resolved via the full IAB GVL (only a few known IDs).
Automatic decoding · Segments separated by . · The demo example shows purposes 1–10 and vendors #1–#4 without names — paste a real string to test partial name resolution (755, 32…).
IAB technical signal only — not a GDPR compliance verdict.
Paste or import up to 5,000 consent strings, then filter by vendor or purpose, view statistics or export CSV. Fully local processing.
Empty lines ignored · whitespace trimmed
Auto-detects the TCF column (base64url, dot-separated segments)
Strings with parse errors
Search type
Separate with commas (e.g. 10,44). Only strings that contain all listed vendors are kept — AND logic (both required, not either/or). Each vendor counts under consent or legitimate interest.
TCF purposes (1–10)
Check one or more purposes. The string must activate every checked box (consent or LI transparency) — AND logic.
Special features
Check one or more options. All must be enabled on the string — AND logic.
How it works
- The string is split into dot-separated Base64url segments; the first is the TCF v2 core.
- Bits are read in IAB order (MSB first within each byte), per the “Consent string and vendor list formats v2” specification.
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CreatedandLastUpdatedare UTC timestamps at the granularity defined by IAB (value × 100 → JavaScript milliseconds). - Vendor IDs refer to the Global Vendor List (GVL); only a handful of common names are resolved locally — not the full GVL yet.
Frequently asked questions
- What is a TCF consent string?
- A compact signal produced by an IAB Europe-registered CMP to carry transparency and consent along the ad supply chain.
- How do I read an IAB consent string?
- Paste the string: the tool shows core fields and, when present, additional segments (disclosed vendors, etc.).
- What information does it contain?
- Purposes, legal-basis signals, vendors, CMP, language, GVL/policy versions, optional publisher restrictions.
- How do I verify vendor consent?
- Check the vendor ID in the decoded core list, then validate business compliance against the GVL and your contracts.
- Does the tool show vendor names (GVL)?
- Partially. It decodes numeric Vendor IDs and enriches a few known names (e.g. Google, Criteo). For most IDs, only the number is shown. Full resolution via the IAB GVL ( vendor-list.json ) — names plus declared purposes per vendor — is planned soon.
- TCF v1 vs v2?
- v1 is obsolete; v2 is the modern format with richer transparency obligations.
- Can I analyze multiple consent strings at once?
- Yes — Bulk analysis tab: up to 5,000 strings via paste or CSV/Excel, with vendor/purpose filters, stats and CSV export. Few public TCF decoders offer this volume locally.
- Does bulk analysis send data to a server?
- No — all processing runs in your browser, like the single-string decoder.