They solve different problems
The most useful thing this page can do is keep you from comparing the wrong attributes. Skyflow is a data privacy vault. Its job is to take a sensitive value (a card number, a Social Security number, a customer record), store it in an isolated, governed vault, and hand your systems an opaque token in its place. When you genuinely need the original value back, an authorized service detokenizes it under policy. The point is to keep the real data out of your application databases while still being able to retrieve it.
Philter does the opposite of “retain and retrieve.” It redacts and de-identifies PII in text as the text moves through your pipeline, so the sensitive content is gone (or encrypted, or replaced with a synthetic value) before it lands in a log, a warehouse, a search index, or a prompt to an LLM. There is no vault to retrieve from because, for most Philter use cases, you never wanted to keep the original in the first place.
So the question is not “which is better.” It is “do I need to retain this value and retrieve it later, or do I need it gone from this data flow?”
When Skyflow is the right tool
If your requirement is to hold sensitive data, just not in your own systems, a vault is the right shape. Classic cases: you must keep a card on file to bill it next month, retain a government ID to satisfy a KYC obligation, or store a customer profile that downstream services occasionally need in the clear under tight access control. Skyflow’s detokenization with fine-grained, policy-based access control is built precisely for that, and it is mostly about structured records rather than free text. If that describes your problem, Philter is not a substitute.
When Philter is the right tool
If your requirement is to remove sensitive data from a flow, a redactor is the right shape. Classic cases: scrub PII out of application logs before they reach your observability stack, de-identify free-text notes before they enter an analytics warehouse, strip identifiers from prompts before they reach a third-party LLM (the Philter AI Proxy does exactly this), or de-identify a training-data set so the original identifiers are never memorized. These are unstructured-text problems where the goal is that the sensitive value does not survive the pipeline. A vault does not solve them, because routing free text through a vault still leaves the surrounding text full of identifiers.
Two further differences matter for regulated buyers:
- Self-hosted and open source. Philter runs entirely inside your perimeter and is open source under Apache 2.0, so the original values never reach a vendor and your team can read the detection logic. Skyflow is managed: even in a bring-your-own-cloud deployment, it is Skyflow’s software operating the vault.
- Reversibility without a vault. When you do need a value to be recoverable, Philter offers format-preserving encryption: the value is encrypted (and decryptable by the key holder) while still looking like the original format, with no separate store to govern. It is a different reversibility model than tokenization, and for many use cases a simpler one.
Many teams use both
These tools are not mutually exclusive, and a mature data-privacy architecture often has a place for each: a vault for the handful of fields you are legally required to retain and retrieve, and a redaction engine for the much larger volume of text and telemetry you simply want cleaned before it spreads. The mistake is using one where you needed the other: storing-and-tokenizing data you only ever wanted gone, or trying to redact your way out of a “we must retrieve this later” requirement.
What to do next
Decide which problem you have first. If you need to retain and retrieve specific structured values under access control, evaluate Skyflow (or a vault generally). If you need to remove or de-identify PII as it flows through logs, analytics, search, training data, or LLM traffic, evaluate Philter. If you are currently using Skyflow for something that is really a redaction problem, the migration guide walks through the architectural translation.